Two things are in this checkin:

Two things are in this checkin:

1) Support for the new "label" module has been added.  It's unfortunate
   about having to make these exceptions but this was the overall cleanest
   way I could think of.

2) All local calculation of pixpath and modpixpath has been removed and
   replaced with a single calculation which is done in setup.php and
   stored in $CFG->pixpath and #CFG->modpixpath.  All graphics should
   use these variables so that themes can easily override them.