Migrate most of main() and and all option parsing to python

Migrate most of main() and and all option parsing to python

configs/test/fs.py:
configs/test/test.py:
    update for the new way that m5 deals with options
src/python/SConscript:
    Compile AUTHORS, LICENSE, README, and RELEASE_NOTES into the
    python stuff.
src/python/m5/__init__.py:
    redo the way options work.
    Move them all to main.py
src/sim/main.cc:
    Migrate more functionality for main() into python.
    Namely option parsing
src/python/m5/attrdict.py:
    A dictionary object that overrides attribute access to
    do item access.
src/python/m5/main.py:
    The new location for M5's option parsing, and the main()
    routine to set up the simulation.

--HG--
extra : convert_revision : c86b87a9f508bde1994088e23fd470c7753ee4c1