- add new AutoboxingCleanUp and UnboxingCleanup classes
- add new usesGivenSignature() static method to ASTNodes class
- add UI support for autoboxing/unboxing to UnnecessaryCodeTabPage
- add new tests to CleanUpTest

Change-Id: Ib859dde76aead8905ab73d53b6e69589b2d2dfb0
Signed-off-by: Fabrice-TIERCELIN <fabrice.tiercelin@yahoo.fr>