Initial incomplete implementation of file transfer.
Add tests to the cmake junit tests.
Fix FileReceiveCallbackTest; run ToxCoreImplTest first.
Removed empty tests.

These will be tested in Alice and Bob tests.
Add wrappers for send custom packet
Merge branch 'pippijn-master'
Add custom packet callback handlers.
Re-register custom packet handlers after load().
Everything is implemented; removed UnsupportedOperationException.
Moved v2 to base and old stuff to v1.
Add travis-ci configuration.
Fix comment
Merge branch 'pippijn-master'