* adds a shell script ./make-macosx-ub.sh that builds Mac OS X Universal Binary
* fixes Mac OS X x86 VM crashes (-mstackrealign)
* adds current working directory to the search path on Mac OS X to make
working with .app bundles easier
* various tweaks to make ioquake3 build against the 10.2 SDK
* changed default OpenAL .dylib location to the path of the one included with
the Framework bundled in 10.4 (for USE_OPENAL_DLOPEN)
* updated to a Universal libSDL-1.2.0.dylib
