Change for:<groupName> tag after save

[Mario Holtmüller]

If you assign a post to a group using the for:<groupName> tag, it should be renamed after saving the post. Otherwise the post could be assigned to the group again after saving it again, if the group has deleted your post before.

[Daniel Zoller]

@jaeschke : was there a reason why we do not change the for tag (compared to the sent/send tag)?

[Robert Jäschke]

There are probably several reasons:

1. We had "for" much earlier than "send".
2. "for" is not a verb, so there is no past tense.
3. The issue should occur quite seldom, so we probably did not think about it or did not care.

I would stick with 3 and ignore this. If it's really an issue, one option would be to remove the tag after successful use. This would violate a bit the principle to not mess with the user's tags, but since we already change "send" to "sent" this shouldn't be much of an issue.