Markers on the minimap/compass

The compass should markers over important entities, such as npc's and houses. When the entities are outside of the compass the markers should appear at the edge. Pretty much like all other compass markers in any other game works.

Note that it might be possible to reuse some of the classes and functionality in the inappropriately named "IngameChatWidget", which is the system used for showing labels over the npc's. There are some performance issues that this system already deals with in a nice way. It would have to be refactored into a better file structure first though.