Built a78407f and failed

Updated project to use jeweler.

by: Luke Redpath | on Dec 01st | commit: a78407f6799322279739c502019aafc0c2cb0b03

Build Output:

rake aborted!
undefined method `extra_rdoc_files' for nil:NilClass
/home/luke/apps/integrity/builds/lukeredpath-clickatell-master/Rakefile:40
(See full trace by running task with --trace)
(in /home/luke/apps/integrity/builds/lukeredpath-clickatell-master)
Jeweler not available. Install it with: gem install jeweler