More lua by request of MuWuum

[softcoder]

- added new lua methods:

void giveStopCommand(int unitId)
bool selectUnit(int unitId)
void unselectUnit(int unitId)
void addUnitToGroupSelection(int unitId,int groupIndex)
void recallGroupSelection(int groupIndex)
void removeUnitFromGroupSelection(int unitId,int groupIndex)
void setAttackWarningsEnabled(bool enabled)
bool getAttackWarningsEnabled()

[MuwuM]

Thank you very much, will test it later. 

Update:

Tested, is working great