Sync address custom field file with main file.

Sync address custom field file with main file.

There is no reason for there being 2 files almost the same for custom data

I plan to use this file more broadly (ie. permit custom data on other entities such as email, phone)
and towards that have aligned the 2 files first.

There are minor differences in display
- read only fields show up as frozen for non-address & now for address too (instead of suppressed)
- post help text shows as full text for address currently but after this it shows as a help-icon
which can be clicked on
- display improvements for file custom fields.

Note that I think making address like the main file makes sense as that will be where deliberate
changes have happened.