set an uniform snapshot version
publish to nexus

The task `build` gets a new step : the `dist` folder is now compressed.

The new task `grunt publish` reads the content of the ivy credentials
(already used by sbt to publish other things) and push the archive of
`dist` to nexus.
fix package name

`bower.json` and `package.json` have different package name...
Merge pull request #3 from dduponchel/nexus_integration

Nexus integration