Gemifying rapricot.

- Added a gemspec to build the gem.
- Moving the rapricot.rb to lib folder as that's what gets called when
you do require 'rapricot'.
MIT License.

Release the gem requires a license. Not sure which license you are
thinking, but MIT is the way to go.
Merge branch 'master' into issue/1
Merge branch 'master' into issue/2
Merge pull request #2 from kunday/issue/2

added mit license
Merge pull request #1 from kunday/issue/1

Gemifying rapricot.