Remove commented-out rcov rake task
Switch from using jeweler to using bundler for building the gem.

This removes jeweler as a dependency and makes the configuration of the gem itself more standard, as bundler is becoming very common to use to build gems.
Renaming the main lib file and directory to match the gem name

Gem naming conventions are a bit loose and unfollowed, but I think for a *-ruby library, it would be best to have the directories and the main file have the same name as the gem, but have the namespace just be Clever.

Reference:
* http://www.intridea.com/blog/2012/3/15/polishing-rubies-part-ii#

Similar examples:
* https://github.com/sosedoff/munin-ruby
* https://github.com/zinenko/vk-ruby
* https://github.com/twilio/twilio-ruby
For rdoc, use the clever-ruby/version file instead of looking for a VERSION file
Specify pessimistically-locked gem versions of the dependencies

This is a best practice for stability:
http://robots.thoughtbot.com/post/35717411108/a-healthy-bundle
Merge pull request #1 from thinkthroughmath/rubygem_conventions

Rubygem conventions