[ticket/13284] Fix request name so users can cc themselves

PHPBB3-13284
[ticket/13284] Set message body in topic form too, so it will be sent

PHPBB3-13284
Merge pull request #3108 from Elsensee/ticket/13284

[ticket/13284] Message body not included in email
Merge branch 'develop-ascraeus' into develop

Conflicts:
	phpBB/styles/subsilver2/template/memberlist_email.html