Use BytesSizeAttribute for mail quota

Descriptive title for this enhancement

Use BytesSizeAttribute for mail quota

Actual behavior

Mail quota input is a simple number input

Expected behavior

Have an advanced input to select KB/MB/GB, as provided by BytesSizeAttribute

Benefits

Would be easier to define large quotas

Possible Drawbacks

None from my point of view

Applicable Issues

I use BytesSizeAttribute for NextCloud plugin (see #6053 (closed))

added plugin-mail label

assigned to @bmortier

changed milestone to %FusionDirectory 1.4

assigned to @cchilliet and unassigned @bmortier

changed due date to November 26, 2020

added PJ1802-0188 label

mentioned in commit 8b692580

This change should be tested with all available mail methods since they interact with the quota field.

added plugin-cyrus plugin-dovecot plugin-renater-partage labels

This broke a test: http://selenium.fusiondirectory.org/screenshots/ImapServiceTest__testIMAPServerForeignKey__2020-12-15T12-46-34.png

added 10m of time spent at 2020-12-15

This is incorrect, gosaMailQuota is supposed to be stored in MiB and is now stored in bytes.

Fixed, it is now storing MiB again

mentioned in issue #6089 (closed)