Update supported Rubies (drop MRI 1.8.7 + 1.9.2, add JRuby 1.7)

.travis.yml

@@ -1,15 +1,9 @@
 language: ruby
 rvm:
-  - 1.8.7
-  - 1.9.2
   - 1.9.3
   - 2.0.0
-  - rbx-18mode
   - rbx-19mode
-  - jruby-18mode
   - jruby-19mode
 matrix:
   allow_failures:
-    - rvm: 2.0.0
-    - rvm: rbx-18mode
     - rvm: rbx-19mode

README.md

@@ -25,7 +25,7 @@ One thing Prawn is not, and will never be, is an HTML to PDF generator. For thos
 
 ## Supported Ruby Versions and Implementations
 
-Because Prawn is pure Ruby and virtually all of its dependencies are maintained by our core team, it should run pretty much anywhere, including Rubinius, JRuby, MacRuby, etc. We officially support MRI {1.8.7, 1.9.2, 1.9.3} and jruby 1.7.x in 1.8 and 1.9 modes, however we will accept patches to fix problems on other Ruby platforms if they aren't too invasive.
+Because Prawn is pure Ruby and virtually all of its dependencies are maintained by our core team, it should run pretty much anywhere, including Rubinius, JRuby, MacRuby, etc. We officially support MRI {1.9.3 and 2.0.0} and jruby 1.7.x in 1.9 mode, however we will accept patches to fix problems on other Ruby platforms if they aren't too invasive.
 
 ## Installing Prawn