Add --outdir option. Didn't call it "-d" since

Add --outdir option.  Didn't call it "-d" since
that's already being used for "detailed cpu".
Needed to add extra function for user script
to pass parsed options back to m5 module.

configs/test/fs.py:
configs/test/test.py:
    Call setStandardOptions().
src/python/m5/__init__.py:
    Add --outdir option.
    Add setStandardOptions() so user script can
    pass parsed options back to m5 module.
src/sim/main.cc:
    Add SWIG-wrappable function to set output dir.

--HG--
extra : convert_revision : 1323bee69ca920c699a1cd1218e15b7b0875c1e5