Fix broken README

[mohan3d]

1. README was written in rst format but had .md extension.
2. Fixed some problems with rst format.
3. Updated documentation section urls (License, contributing).
4. Updated direct install using pip and repository url.
5. Fixed Travis url.

If you try to install directly from the repository pip will not be able to install since the repository url must be prefixed with git+

even when you fix this installation will fail with this message. (look at this line this is the problem we don't have a README.rst file)
IOError: [Errno 2] No such file or directory: 'README.rst'

Travis url is linking for the old repository (build status unknown).