at: use last non-blank line
at&cron: confirm screen is blank!
at&cron: "edit" screen

big "close" button is unnecessary.
"job details" for at is unnecessary.
nasty warnings on stderr.


* porting and port testing
* add "refresh" buttons? (or refresh automatically?)
* rescan before committing.  mark each entry as to-be-deleted, to-be-added,
  or unchanged, and apply the changes appropriately while rescanning.
* preserve comments/spacing in cron files? (nah)
* add some way to kill launched jobs (separate helper program?)
* (better) validators in the druids
* zero-pad the minute spinners.  Does this mean abandoning GtkSpinButton?
* add AM/PM to hour spinners
* check for memory and file descriptor leaks
* add special classes of jobs like "send an e-mail" or "pop up a message"
  or "play a sound", or apps from Gnome start menu.
* drag and drop from Gnome start menu onto main screen (start a new job
  pre-filled with the program) or to "pick program" screen
