use Travis CI to deploy GitHub releases

closes #3775
Added a description to the pillbox
Renamed Developer Mode to Cheats for consistency.
Added notion that it disables FoW as well to Disable Shroud cheat option.
Fixes crash when joining multiplayer lobby

Fixes crash when joining a multiplayer lobby caused by recent spawn
choice changes.
Merge pull request #5352 from Squiggles211/mp_lobby_fix

Fixes lobby crash when joining MP game
Adjust the singleplayer menu button positions to remove unnecessary mouse movement.
Fix incorrect font in spawn selector.
Go back to the smaller circle for the colorpicker.
fix closing slots not removing bots properly
Use smaller spawn points.
Merge pull request #5355 from Mailaender/missing-bot-slot-sync

Fixed closing slots not removing bots properly
Merge pull request #5356 from pchote/td-ui-polish

TD UI Polish
Merge pull request #5348 from reaperrr/ra-shroud-cheatlabel

Closes #5167
Merge pull request #5343 from Saticmotion/bleed

Fixes #5050
Update colorpicker circle to match spawn points.
Merge pull request #5357 from pchote/td-ui-polish

UI polish fixup
rename OpenRA.Support.Random aka XRandom to MersenneTwister
Merge pull request #5341 from Mailaender/travis-deploy

Setup Travis CI to deploy GitHub releases
Merge pull request #5359 from Mailaender/mersenne-twister

Renamed OpenRA.Support.Random aka XRandom to MersenneTwister
Added in code for Tech Levels using prereqs
and fixed up some kinks of the old system