Added contributors widget (#1098)

Fixes #44 

Following [this answer](https://stackoverflow.com/a/19200303/4496364) I managed to get this via Github API:

![](https://upload.cc/i1/2018/07/04/n4zkhJ.png)

I roughly followed Mozilla's [docs page](https://developer.mozilla.org/en-US/docs/Web/HTML) design and their contributors listing.
Some users don't have the "author" field. Probably deleted their profile?  
So, the fallback is `commit.commit.committer.name` which is, I suppose, always present because of Git...  

Also, if the author isn't present, image icon is generated with https://github.com/identicons. Example here is Ghildiyal user.

Currently, I added this to tour only. IDK did you guys intend to put these on each page?  
If so, there could be some problems with getting page URL from Github. IDK if all of them follow same pattern as "tours"..

Author: sake92

_includes/contributors-list.html

@@ -0,0 +1,4 @@
+<div class="content-contributors">
+    <h3>Contributors to this page:</h3>
+    <div id="contributors" class="contributors-container"></div>
+</div>

_includes/inner-page-main-content.html

@@ -3,6 +3,8 @@
 		<div class="content-primary">
 			<div class="inner-box">
 				{{content}}
+
+				{% include contributors-list.html %}
 			</div>
 		</div>
 

_layouts/cheatsheet.html

@@ -30,6 +30,8 @@
             {% endfor %}
           </ul>
         {% endif %}
+
+        {% include contributors-list.html %}
 			</div>
 		</div>
 	</div>

_layouts/glossary.html

@@ -8,6 +8,8 @@
 		<div class="content-primary documentation glossary">
 			<div class="inner-box">
 				{{content}}
+
+				{% include contributors-list.html %}
 			</div>
 		</div>
 

_layouts/multipage-overview.html

@@ -9,6 +9,8 @@
 		<div class="content-primary documentation">
 			<div class="inner-box">
 				{{content}}
+
+				{% include contributors-list.html %}
 			</div>
 		</div>
 

_layouts/singlepage-overview.html

@@ -8,6 +8,8 @@
 		<div class="content-primary documentation">
 			<div class="inner-box">
 				{{content}}
+
+				{% include contributors-list.html %}
 			</div>
 		</div>
 

_layouts/style-guide.html

@@ -9,6 +9,8 @@
 		<div class="content-primary documentation style-guide">
 			<div class="inner-box">
 				{{content}}
+
+				{% include contributors-list.html %}
 			</div>
 		</div>
 

_layouts/tour.html

@@ -20,6 +20,8 @@
                     <a href="{{page.next-page}}.html"><strong>next</strong> &rarr;</a>
                     {% endif %}
                 </div>
+
+                {% include contributors-list.html %}
             </div>
 		</div>
 

_sass/layout/content-contributors.scss

@@ -0,0 +1,22 @@
+.content-contributors {
+    .contributors-container {
+        display: flex;
+        flex-wrap: wrap;
+        align-items: center;
+        div {
+            margin: 5px;
+            a {
+                vertical-align: middle;
+                padding: 3px;
+                text-decoration: none;
+            }
+            img {
+                vertical-align: middle;
+                width: 35px;
+                height: 35px;
+                margin-bottom: 0;
+                border-radius: 7px;
+            }
+        }
+    }
+}

resources/css/style.scss

@@ -54,7 +54,8 @@
 @import 'layout/books';
 @import 'layout/training-events';
 @import 'layout/blog';
-@import 'layout/download'; // COMPONENTS
+@import 'layout/download';
+@import 'layout/content-contributors'; // COMPONENTS
 //------------------------------------------------
 //------------------------------------------------
 @import 'components/buttons';

resources/js/functions.js

@@ -521,4 +521,85 @@ $(document).ready(function(){
         $("html, body").animate({ scrollTop: 0 }, 600); 
         return false; 
     }); 
-});
+});
+
+//Contributors widget
+// see https://stackoverflow.com/a/19200303/4496364
+$(document).ready(function () {
+  let githubApiUrl = 'https://api.github.com/repos/scala/docs.scala-lang/commits';
+  let identiconsUrl = 'https://github.com/identicons';
+  /* - we need to transform "/tour/basics.html" to "_ba/tour/basics.md"
+   * - some files aren't prefixed with underscore, see rootFiles
+   * - some files are placed in _overviews but rendered to its folder, see overviewsFolders
+   */
+  
+  let rootFiles = ['getting-started', 'learn', 'glossary'];
+  let overviewsFolders = ['FAQ', 'cheatsheets', 'collections', 'compiler-options',
+    'core', 'jdk-compatibility', 'macros', 'parallel-collections',
+    'plugins', 'quasiquotes', 'reflection',
+    'repl', 'scaladoc', 'tutorials'
+  ];
+
+  let thisPageUrl = window.location.pathname;
+  // chop off beginning slash and ending .html
+  thisPageUrl = thisPageUrl.substring(1, thisPageUrl.lastIndexOf('.'));
+  let isRootFile = rootFiles.some(rf => thisPageUrl.startsWith(rf));
+  let isInOverviewsFolder = overviewsFolders.some(of => thisPageUrl.startsWith(of));
+  if(isRootFile) {
+    thisPageUrl = thisPageUrl + '.md';
+  } else if(isInOverviewsFolder) {
+    thisPageUrl = '_overviews/'+ thisPageUrl + '.md';
+  } else {
+    thisPageUrl = '_' + thisPageUrl + '.md';
+  }
+  
+  let url = githubApiUrl + '?path=' + thisPageUrl;
+  $.get(url, function (data, status) {
+    if(!data || data.length < 1) {
+      $('.content-contributors').html(''); // clear content
+      return false; // break
+    }
+    let contributorsUnique = [];
+    data.forEach(commit => {
+      // add if not already in array
+      let addedToList = contributorsUnique.find(c => {
+        let matches = c.authorName == commit.commit.author.name;
+        if (!matches && commit.author) {
+          matches = c.authorName == commit.author.login;
+        }
+        return matches;
+      });
+
+      if (!addedToList) {
+        // first set fallback properties
+        let authorName = commit.commit.author.name;
+        let authorLink = '';
+        let authorImageLink = identiconsUrl + '/' + commit.commit.author.name + '.png';
+        // if author present, fill these preferably
+        if (commit.author) {
+          authorName = commit.author.login;
+          authorLink = commit.author.html_url;
+          authorImageLink = commit.author.avatar_url;
+        }
+        contributorsUnique.push({
+          'authorName': authorName,
+          'authorLink': authorLink,
+          'authorImageLink': authorImageLink
+        });
+      }
+    });
+
+    let contributorsHtml = '';
+    contributorsUnique.forEach(contributor => {
+      let contributorHtml = '<div>';
+      contributorHtml += '<img src="' + contributor.authorImageLink + '">';
+      if (contributor.authorLink)
+        contributorHtml += '<a href="' + contributor.authorLink + '">' + contributor.authorName + '</a>';
+      else
+        contributorHtml += '<a>' + contributor.authorName + '</a>';
+      contributorHtml += '</div>';
+      contributorsHtml += contributorHtml;
+    });
+    $('#contributors').html(contributorsHtml);
+  });
+});