Force TechRacer maps when image map is selected. Fixes Google Code issue #882
If you start a TechRacer map with an image map selected, the resulting map will likely to be completely unplayable.
So this commit disables this.
f3e903ace2d3
Make hedgewars frontend not change scheme/weps to Default if script cfg doesn't match a known scheme. That is, will leave on whatever is selected. Also set a bunch of schemes where we don't care what the scheme/weps are to *