Fix the CFLAGS feature.  This is useful for making it easier to use external libraries in XMDS scripts.

git-svn-id: svn+ssh://svn.code.sf.net/p/xmds/code/trunk/xpdeint@2823 41b19578-b77a-4e3b-9682-c8570d237623
Revert previous patch as it broke things.

git-svn-id: svn+ssh://svn.code.sf.net/p/xmds/code/trunk/xpdeint@2824 41b19578-b77a-4e3b-9682-c8570d237623