[Gtkradiant] first 1.3 experimental setup for win32

[Timothee Besset]

Finally got around to build and upload it:
http://zerowing.idsoftware.com/nightly/GtkRadiantSetup-1.3.5-dev.exe

This is clearly a developer thing at this point. I have included all 
games, but only checked that Q3 and RTCW started. HL may or may not be 
working. Other games are missing a synapse.config

I am uploading this build hoping to bootstrap some effort to start 
stabilizing 1.3 and go towards an alpha release soon.

TTimo