editor: add ability to create additional types of elements

[jlillis]

Is your feature request related to a problem? Please describe.
It is not currently possible to create blips, radar areas, colshapes, or water elements via the map editor.

Describe the solution you'd like
The map editor should allow for the creation of these elements just like it objects, markers, pickups, and other elements.

Describe alternatives you've considered
N/A

Additional context
Blips & radar areas will require the addition of some sort of 2D map view for editing. In adding this 2D view, there are also a few bonus features that could be considered:

• Filters to show the location of placed map objects
• The ability to drag/move the camera to a position on the map

A transformation widget should be added to allow mappers to manipulate colshapes & water elements.

Some sort of visualization will need to be given to colshapes to make them visible and selectable in the editor.