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.