Add wizard support to coinffeine-gui

**Description:** bump to JavaFX 8 and introduce support for wizards. Introduce the initial setup wizard (with pending implementation of its wizard steps).
**Testing:** manual testing
![image](https://cloud.githubusercontent.com/assets/259587/3248302/5f7d3ee4-f18d-11e3-9419-3f386fec2165.png)
**Coverage:** I'm afraid we are going to be close to 0% of coverage on this module.