Add mounting for soldiers onto tactical subs
Resolve issue55: Add unloading from subs

Unloads soldiers at sub's position, so it won't work over terrain.
Merge branch 'issue55' into develop
Merge branch 'develop' of
https://github.com/gsnorton/CS-547-Project-Two.git into develop

Conflicts:
	atlantis/issues.mkd
	atlantis/src/atlantis/AtlantisEntity.java