Add klage option to header if possible

[stefanw]

This should probably have translation strings.

And I noticed that in froide-legalaction the permission checking for Klageautomat should use the can_write_foirequest to also take team permissions into account.

[MagdaN]

hmm, I did not use translateable string as none of the strings in this template are translateable, should I better make all strings translateable then?

[stefanw]

You were right. I removed the translation (as it also caused an ugly conflict).