Issue #66: Add template for search

[TomoTsuyuki]

Include a template area for searching.

Testing instruction

• Go to "Site administration" > "General" > "Advanced features".
• Enable Global search.
• Go to "Site administration" > "Plugins" > "Activity modules" > "CMS" > "Manage content types"
• Click "Add new content type".
• Set "Template test" in "Name", "test" in "ID Number", "Template test" in "Name" under "Activity fields", and "{{name}} Testsearchstring" in "Content" under "Activity field".
• Click "Save and display" and confirm the "Some name Testsearchstring" is in "Preview"
• Create a course.
• Turn on "Edit mode" and add "Template test" CMS activity.
• Go to "Site administration" > "Plugin" > "Search" > "Search areas".
• Click "Gradual reindex" for cms activity, and run "Global search indexing" schedule task.
• Search "Testsearchstring" in global search box.
• Confirm the "Testsearchstring" is in the result.