Forum post are anonymous by default

for the forum it can be activated in the administration that anonymous entries are allowed.
it should also be possible to activate anonymous users by default for every forum entry.
in the forum entry, the pseudonym is activated by default. the user needs to enter a pseudonym and can save it. it is still possible to deactivate pseudonym and write entry with the user name.

--> add this default option to administration, configuration in the course element and in every forum entry

Intern: CL-664