Manual User activation

A user is now put in a sort of suspension on signup. It's not the same as a regular suspension though. This was done to be able to distinguish between new signups and suspended users.

Please try this and tell me what doesn't work. Things to be done are at the very least:

- proper localization (translation of new phrases into german and french?)
- send an email to an activated user (I couldn't find out how/where it's done when sending out the activation email.)