The option --atlas is oddly different than any other feature flag,
change it to be in line with the others and enable it by default. The
new option is --without-atlas.
As the WX binaries aren't precompiled for Windows automagically disable
atlas there for users running the batchfile through filemanger if WX is
missing.
On *nix not providing a valid wx-config whith enabled atlas is
considered an error.
Fixes: #6401
Signed-off-by: Ralph Sennhauser <ralph.sennhauser@gmail.com>
Ralph Sennhauser
949d5f8c0b