add support for bower wip

[gregory]

this is regarding the PR #35 that has been closed. it's a WIP at 90%
@did I think you might be faster to solve the small issue that persist when pushing on the engine.
could you have a quick look?

[gregory]

@did this is working for me in dev and production. but having trouble when i try to push a second time... could you check? :)

[gregory]

I didn't took the time to fix the failing specs since i was a little on the rush to deliver.
If anyone is interested in leveraging the power of bower for the assets, please fix the specs.
I'm pretty busy lately so wont have to time to dig back into that right now.
If anyone works on this, please reply to this so that we know someone is on it.

FYI, this code worked for me to push assets from bower.

You'd just have to make sure to have valid bower.json files with a main: ['css/file.css', 'js/file.js'] that points to your files.