Fix hilarious backslash bug (#245)

Check when submitting a BibID that it is an Integer.  This fixes #245.

Disables/enables the save/don't save buttons appropriately on the Identify form, and reports errors when finding catalogue numbers inside a styled div.

Also fixes JS bug where keydown would always be interrupted and users couldn't do ordinary browser key shortcuts that we weren't over riding (like control/command + R)