Include RST in the languages list

lib/linguist/languages.yml

@@ -1364,6 +1364,12 @@ Rebol:
 Redcode:
   primary_extension: .cw
 
+reStructuredText:
+  type: prose
+  lexer: Text only
+  wrap: true
+  primary_extension: .rst
+
 RobotFramework:
   type: programming
   primary_extension: .robot

test/test_language.rb

@@ -369,7 +369,7 @@ class TestLanguage < Test::Unit::TestCase
   end
 
   def test_by_type
-    assert_equal 6, Language.by_type(:prose).length
+    assert_equal 8, Language.by_type(:prose).length
   end
 
   def test_colorize