Add support for raw/verbatim blocks in Jinja/Twig

Jinja provides a `raw` tag and Twig provides a `raw` tag in its
1.x version and a `verbatim` one in newer versions.

To make the code simple, since the Twig lexer extends from the Jinja
one, the latter holds the logic for both tags.

lib/rouge/lexers/jinja.rb

@@ -31,6 +31,10 @@ def self.pseudo_keywords
         @@pseudo_keywords ||= %w(true false none True False None)
       end
 
+      def self.raw_keywords
+        @@raw_keywords ||= %w(raw verbatim)
+      end
+
       def self.word_operators
         @@word_operators ||= %w(is in and or not)
       end
@@ -113,7 +117,10 @@ def self.word_operators
 
       state :statement do
         rule /(\w+\.?)/ do |m|
-          if self.class.keywords.include?(m[0])
+          if self.class.raw_keywords.include?(m[0])
+            token Keyword
+            goto :raw
+          elsif self.class.keywords.include?(m[0])
             groups Keyword
           elsif self.class.pseudo_keywords.include?(m[0])
             groups Keyword::Pseudo
@@ -133,6 +140,25 @@ def self.word_operators
 
         rule /\%\}/, Comment::Preproc, :pop!
       end
+
+      state :raw do
+        mixin :text
+
+        rule /\%\}/ do
+          token Comment::Preproc
+          push :raw_block
+        end
+      end
+
+      state :raw_block do
+        rule %r{(\{\%)(\s+)(endverbatim|endraw)(\s+)(\%\})} do
+          groups Comment::Preproc, Text::Whitespace, Keyword, Text::Whitespace,
+                 Comment::Preproc
+          pop!(2)
+        end
+
+        rule /(.+?)/, Text
+      end
     end
   end
 end

spec/visual/samples/jinja

@@ -20,4 +20,12 @@ Hello {{ user.name|capitalize }} !
 {# A comment on multiple lines
    to hide a piece of code or whatever #}
 
+{% raw %}
+  {% for item in seq %}
+    <li>{{ item }}</li>
+  {% endfor %}
+{% endraw %}
+
+{% raw %} One line {{ raw }} block {% endraw %}
+
 {% include 'footer.html' %}

spec/visual/samples/twig

@@ -12,4 +12,12 @@
   {% flush %}
 {% endif %}
 
+{% verbatim %}
+  {% for item in seq %}
+    <li>{{ item }}</li>
+  {% endfor %}
+{% endverbatim %}
+
+{% verbatim %} One line {{ verbatim }} block {% endverbatim %}
+
 {% include 'footer.html' %}