[Groups] make group description/responses translatable

[rallek]

Q	A
Zikula Version	1.4.5RC1
PHP Version	5.5.30

Expected behavior

I want to make a description in german and english but there is only an not translatable field available

[rallek]

also the answers if you deny or accept a group membership should be possible in different languages:

[Guite]

Closing as won't fix as applications are to be removed.