Merge branch 'update-redcarpet' into 'master'

Update redcarpet gem. Fixes gem memory leak

Fixes #2773 

See merge request !1607

Gemfile

@@ -94,7 +94,7 @@ gem "seed-fu", '~> 2.3.5'
 gem 'html-pipeline', '~> 1.11.0'
 gem 'task_list',     '~> 1.0.2', require: 'task_list/railtie'
 gem 'github-markup', '~> 1.3.1'
-gem 'redcarpet',     '~> 3.3.2'
+gem 'redcarpet',     '~> 3.3.3'
 gem 'RedCloth',      '~> 4.2.9'
 gem 'rdoc',          '~>3.6'
 gem 'org-ruby',      '~> 0.9.12'

Gemfile.lock

@@ -539,7 +539,7 @@ GEM
       trollop
     rdoc (3.12.2)
       json (~> 1.4)
-    redcarpet (3.3.2)
+    redcarpet (3.3.3)
     redis (3.2.1)
     redis-actionpack (4.0.0)
       actionpack (~> 4)
@@ -881,7 +881,7 @@ DEPENDENCIES
   rails (= 4.1.12)
   raphael-rails (~> 2.1.2)
   rdoc (~> 3.6)
-  redcarpet (~> 3.3.2)
+  redcarpet (~> 3.3.3)
   redis-rails (~> 4.0.0)
   request_store (~> 1.2.0)
   rerun (~> 0.10.0)