Partially revert "Cleanup: removed dead code"

This partially reverts commit 4df98e21be292f24f5c94b4c6b63c0accf4ffd72.

Was necessary since we want to keep open the possibility to have several
files in a terminology project.
Reverse hardcoded URLs
Reverse URLs for util.edit instead of hardcoding them
License cleanups
Get rid of the single quotes on HTML code
Replace hardcoded URLs with url template tag
Cleanups: multiple minor cleanups

ctx, form fields, imports order, shorten calls, blank lines, remove try
block, ...