removed C extensions requirement to support Rubinus and help with Jruby, and ...

With a trivial fix to tests, rubinus now works.

Jruby no longer supports C extensions ( https://github.com/jruby/jruby/wiki/C-Extension-Alternatives ), so I changed server from thin to puma. The tests now at least run with Jruby (unfortunately with many failures).

Also includes Add icon badges to README file for travis-ci, codeclimate, gemnasium

Includes pull request #121 (Various fixes so tests pass reliably under ruby 1.8.7 and 1.9.3 plus enhancements)