new colors for app and user menu + new loading animations

As proposed in https://github.com/owncloud/themes/pull/7.
Screenshots say more than 1000 words:

![header_bar_menu](https://cloud.githubusercontent.com/assets/2237222/3692623/5dfca54e-135e-11e4-9579-d37fe604c79d.png)

![loading_animation](https://cloud.githubusercontent.com/assets/2237222/3710774/8e62cf90-14aa-11e4-8fd0-6e2b194338fa.png)