Steroids for our floating action button

[thomaseizinger]

This PR transforms our FAB into a menu that allows the user to choose from several actions.

Before	After

For now, I have chosen to directly activate the button and simply disable the action that is not yet available ('Pay someone'). Like a little hint that shows the user that this is available soon :)

Main features:

• No positioning hacks with JS. Functionality is solely achieved with CSS3 transformations and animations => Browser consistent behavior, even IE displays the menu correctly!
• Menu can be deactivated using the back-button (neat for mobile!)
• Menu can be deactivated with a click outside of the controls (on the transparent background)
• Menu can be deactivated by clicking on the initial button again (that one was easy :D)
• Up to 5 items inside the menu. (Configurable, but material-design spec recommends to not put more than 5 actions inside of a FAB.)
• FAB component itself is completely stateless. All state is controlled from the outside.
• Material-design spec compliant animations. (Durations as well as timing functions)

Fixes #65.

[duffleit]

Looks perfect, I love it. Solve conflicts and merge it :+1: