Minor fixes and more documentation

Hi guys,

Thanks for the grunt plugin!

Here's my contribution if you need:

- Fix a bug if you specify a tree hierarchy in the files configuration ```**/*```, the task was keeping the directories as files.
- Added more documentation about the ```options``` to pass to the task
- Changed the default ```processName``` to default the keys of each template to the dir hierarchy it is in (removing any trailing **/templates/ path)
- A .travis.yml file to enable CI and the badge in the readme

Have fun!