Color blindness friendliness

[allejo]

Under Display Settings add a new option for choosing a colorblind friendly color palette. There were changes made a while back that allowed for modifications to colors on the radar and such, so there should be an option in the menu to change these values to defaults based on the type of color blindness.

Secondly, are tank skins affected too? How should the client behave? Should we just provide different skins for players to download and replace it themselves? Should clients come bundled with color blindness friendly skins (is this possible in 2.4) and allow for swapping?

[macsforme]

This is loosely related to #12.