Fixing travis-ci build error

Updated Travis-CI to add support for 
* 2.0.0
* 2.1.0 (Allow for this failure which is due to bundler and not this gem)

Updated ReadMe to move the build status badge to the top - where it is typically found.

Also, might wanna think about adding [coveralls.io](https://coveralls.io/) which is free and works well with travis-ci!

Hasnain