Switch to java7

Cleaned up POMs. Changed SPIProcessor to work with java 7. Increased versions of some frameworks:

- GIN: 1.5.0 &rarr; 2.0.0
- GWTP: 0.7 &rarr; 1.0-RC-2
- GWT-Log: 3.1.8 &rarr; 3.2.1
- JUnit: 4.8.1 &rarr; 4.11

Tried to use latest version of GWT (2.5.1), but failed with an error in full compile.