Make EditTabs able to delay incoming calls until after code load.
Make EditTabs able to delay incoming calls until after code load.

Add a private list of callbacks to be fired once the code has been
loaded, and a boolean which stores the load state. New files are of
course loaded as soon as they're created.

jmorse/cyanide,jmorse/cyanide,jmorse/cyanide,jmorse/cyanide