Merge branch 'fix_unit_type' into 'master'

python-api-src/lib_replay_unit.cpp

python-api-src/lib_tech_tree.cpp

python-api-src/library.cpp

src/IDABot.cpp

src/IDAReplayObserver.cpp

src/IDAReplayObserver.h

src/ReplayUnit.cpp

src/ReplayUnit.h

src/TechTree.cpp

src/TechTree.h

src/Unit.cpp

src/UnitType.cpp

src/UnitType.h