Fix #498

Ruby 1.8.7 and ri can't deal with <!-- appearing in documentation.
Please upgrade to the latest Ruby if you're able to.

README.md

@@ -528,8 +528,8 @@ your changes merged back into core is as follows:
     $ gem push gollum-X.Y.Z.gem
     
 ## BUILDING THE GEM FROM MASTER
-    $ gem uninstall -aix gollum
+    $ gem uninstall -ax gollum
     $ git clone https://github.com/github/gollum.git
     $ cd gollum
     gollum$ rake build
-    gollum$ gem install pkg/gollum*.gem
+    gollum$ gem install --no-ri --no-rdoc pkg/gollum*.gem

gollum.gemspec

@@ -5,7 +5,7 @@ Gem::Specification.new do |s|
   s.required_ruby_version = ">= 1.8.7"
 
   s.name              = 'gollum'
-  s.version           = '2.1.8'
+  s.version           = '2.1.10'
   s.date              = '2012-08-30'
   s.rubyforge_project = 'gollum'
 

lib/gollum.rb

@@ -23,7 +23,7 @@ require File.expand_path('../gollum/web_sequence_diagram', __FILE__)
 require File.expand_path('../gollum/frontend/uri_encode_component', __FILE__)
 
 module Gollum
-  VERSION = '2.1.8'
+  VERSION = '2.1.10'
 
   def self.assets_path
     ::File.expand_path('gollum/frontend/public', ::File.dirname(__FILE__))

lib/gollum/markup.rb

@@ -591,12 +591,18 @@ module Gollum
     #########################################################################
 
     # Extract metadata for data and build metadata table. Metadata
-    # is content found between `<!-- ---` and `-->` markers, and must
+    # is content found between markers, and must
     # be a valid YAML mapping.
     #
+    # Because ri and ruby 1.8.7 are awesome, the markers can't
+    # be included in this documentation without triggering
+    # `Unhandled special: Special: type=17`
+    # Please read the source code for the exact markers
+    #
     # Returns the String of formatted data with metadata removed.
     def extract_metadata(data)
       @metadata ||= {}
+      # The markers are `<!-- ---` and `-->`
       data.gsub(/\<\!--+\s+---(.*?)--+\>/m) do
         yaml = @wiki.sanitizer.clean($1)
         hash = YAML.load(yaml)