fix Editor navbar issues

Fixes long standing Mantis issue:
http://archub2.mimas.ac.uk/mantis/view.php?id=6001
admin: gitignore PyCharm artefacts
strip all tags from <titleproper> in Editor

Mantis issue 846

Some tags that are permitted in <unittitle> are NOT permitted in
<titleproper>. Stript out all tags from <titleproper> to remove
risk of generating invalid EAD due to this.
update Editor delete draft warning text

Mantis issues 804, 843
replace Editor NRA place names link with GeoNames

Mantis issue 780
allow multiple <extent> in Editor

Mantis issue 707