Add group system

Initial commit, not tested in multiplayer yet. Some revisions still left
to do.

SQF/dayz_code/groups/getCrew.sqf

@@ -0,0 +1,8 @@
+private "_crew";
+
+_crew = [];
+{
+	_crew set [count _crew, if (alive _x) then {name _x} else {"unknown"}];
+} count crew _this;
+
+format ["%1%2",typeOf _this,_crew]