Merge pull request #60 from Rutherther/feat/combat-v1

Make combat nonblocking, make multiple queues for distinct operations

fix(combat): walk in correct range for zone skills

fix(combat): look at correct entity on map when determining whether attack technique should continue

fix(combat): prevent using passive skills in simple attack technique

feat(combat): update operations to be non-blocking, add support for handling waiting

feat(game): put friends, group, inventory, skills in Game instead of Character

feat(combat): support self targeted and area skills

Merge pull request #32 from Rutherther/combat

Add combat extension

feat(combat): remove item selector from simple attack technique

fix(combat): null skill after it was used

feat(combat): make target id long

feat(combat): return current target from combat technique

docs(combat): add missing documentation

feat(combat): add simple attack combat technique