Replaced ENGINE_LIB,ENGINE_INC,AD_LIB,AD_INC.
local.conf migration might be necessary, but see local.conf.example
JAVA_HOME now guessed on linux
make clean now cleans .so and .dylib always (now you can share the workspace between linux and mac)
All calls to an Engine obj are locking the mutex for their respective object.
A unordered_map holds the mutex per java obj hash. The mutexes are created/deleted in constructor/destructor of an engine object.
A global mutex is being locked for write operations on the unordered map (not thread safe).
Cleanup of #includes