Add option to sepcify rubygems url now that download location has changed.

README.rst

@@ -33,6 +33,10 @@ gems
     list of gem package names, also you can specify gem version, example:
     ``sass==3.1.1``.
 
+url
+    rubygems zip download url, if not specified, recipe will try to find most
+    recent version.
+
 version
     rubygems version, if not specified, recipe will try to find most recent
     version.

rubygems.py

@@ -29,6 +29,7 @@ class Recipe(object):
 
         self.gems = options['gems'].split()
         self.version = options.get('version')
+        self.url = options.get('url')
         # Allow to define specific ruby executable. If not, take just 'ruby'
         self.ruby_executable = options.get('ruby-executable', 'ruby')
 
@@ -80,6 +81,12 @@ class Recipe(object):
         }
 
     def _get_latest_rubygems(self):
+        if self.url:
+            version = self.version
+            if not version:
+                version = re.search(r'rubygems-([0-9.]+).zip$', self.url).group(1)
+            return (self.url, version)
+
         if self.version:
             return ('http://production.cf.rubygems.org/rubygems/'
                     'rubygems-%s.zip' % self.version, self.version)