Fix:  bower.json should *not* contain .style.css in the main section.

.style.css was wrongly added (https://github.com/a5hik/ng-sortable/commit/b6ece33858b960971d28510160435a30d24a3c10) to the main section.   it should **not** be there.
See: https://github.com/a5hik/ng-sortable/pull/47 for why.  the whole idea is that your style is not forced in to the app,  it is optional.