Whether running locally or via PBS, $PATH should now be handled in your
user's environment.
This also fixes problems like PYTHONPATH on the new blast nodes being
wrong (because they are x86_64 and the frontends are i686).
Note that you can actually start Galaxy without having an eggs dir now.
distribution point and copy them to Galaxy's eggs/ directory.
fetch_eggs_tarball.py and check_python_platform.py are mostly for offline
systems. fetch_eggs_tarball.py fetches eggs for your platform (or a
specified platform) and then tars them up, for copying to another system.
check_python_platform.py returns the string for your platform/interpreter
that will be used to download from the egg distribution site.