Added a back door so we can debug Rappture applications running
in the nanoHUB environment.
Added format and label controls to the axes of an XY plot.
Added a <molecule><about><emblems> directive, a boolean control
indicating whether or not the molecule viewer should show the
atom labels by default. If missing or "off", the labels are
turned off. To turn labels on by default, this must be set
to a boolean true value.
Fixed the packing bug that was causing tabbed notebooks to be
the wrong size (size of last page, rather than max overall size).
Added -state option to comboboxes, so they can be disabled.
Added a grab stack, so that when a balloon dialog has the grab
and a combobox steals it away, the balloon gets it back.
