Map System Code Refactor (#204)

* Removes static `IoCManager` service locator calls from `Robust.Shared.Map` namespace.
* Misc code cleanup and filling out doc comments for Map classes.
* Added Union and Intersect methods to Box2.
* Any touched component was converted from static IoC calls to field injection.

Sibling PR to https://github.com/space-wizards/RobustToolbox/pull/796.

Resources/Groups/groups.yml

@@ -43,4 +43,6 @@
   - toggleready
   - spawn
   - delete
+  - tp
+  - tpgrid
   CanViewVar: true