Bump Ruby (2.2) and Rails (4.2)

Gemfile

@@ -1,5 +1,5 @@
 source 'https://rubygems.org'
-ruby '2.1.5'
+ruby '2.2.0'
 
 gem 'thor'
 gem 'pry', '~> 0.9.12'

Gemfile.lock

@@ -1,14 +1,14 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (4.1.8)
-      i18n (~> 0.6, >= 0.6.9)
+    activesupport (4.2.0)
+      i18n (~> 0.7)
       json (~> 1.7, >= 1.7.7)
       minitest (~> 5.1)
-      thread_safe (~> 0.1)
+      thread_safe (~> 0.3, >= 0.3.4)
       tzinfo (~> 1.1)
     backports (3.6.4)
-    better_errors (2.0.0)
+    better_errors (2.1.0)
       coderay (>= 1.0.0)
       erubis (>= 2.6.6)
       rack (>= 0.9.0)
@@ -22,7 +22,7 @@ GEM
     erubis (2.7.0)
     ethon (0.7.1)
       ffi (>= 1.3.0)
-    eventmachine (1.0.3)
+    eventmachine (1.0.4)
     execjs (2.2.2)
     ffi (1.9.6)
     highline (1.6.21)
@@ -30,11 +30,11 @@ GEM
     html-pipeline (1.11.0)
       activesupport (>= 2)
       nokogiri (~> 1.4)
-    i18n (0.6.11)
+    i18n (0.7.0)
     json (1.8.1)
     method_source (0.8.2)
     mini_portile (0.6.1)
-    minitest (5.4.3)
+    minitest (5.5.0)
     multi_json (1.10.1)
     nokogiri (1.6.5)
       mini_portile (~> 0.6.0)
@@ -46,7 +46,7 @@ GEM
       coderay (~> 1.0)
       method_source (~> 0.8)
       slop (~> 3.4)
-    rack (1.5.2)
+    rack (1.6.0)
     rack-protection (1.5.3)
       rack
     rack-test (0.6.2)
@@ -83,7 +83,7 @@ GEM
       ethon (>= 0.7.1)
     tzinfo (1.2.2)
       thread_safe (~> 0.1)
-    uglifier (2.5.3)
+    uglifier (2.6.0)
       execjs (>= 0.3.0)
       json (>= 1.8.0)
     unix_utils (0.0.15)

README.md

@@ -23,7 +23,7 @@ Unless you wish to use DevDocs offline or contribute to the code, I recommend us
 
 DevDocs is made of two separate pieces: a Ruby scraper responsible for generating the documentation and index files, and a JavaScript front-end powered by a small Sinatra app.
 
-DevDocs requires Ruby 2.1.5 and a JavaScript runtime supported by [ExecJS](https://github.com/sstephenson/execjs#readme) (included in OS X and Windows; [Node.js](http://nodejs.org/) on Linux). Once you have these installed, run the following commands:
+DevDocs requires Ruby 2.2.0 and a JavaScript runtime supported by [ExecJS](https://github.com/sstephenson/execjs#readme) (included in OS X and Windows; [Node.js](http://nodejs.org/) on Linux). Once you have these installed, run the following commands:
 
 ```
 git clone https://github.com/Thibaut/devdocs.git && cd devdocs