replaces spaces in givenname when enforcing daemon recipient policy. to avoid crate mailboxes with spaces

Summary: When daemon recipient policy isn't disabled and a given name contains white spaces, kolab webadmin generates correct email addresses but pykolab tries to rewrite it to a email address containing white spaces.

Reviewers: PyKolab Developers, machniak, vanmeeuwen

Reviewed By: machniak

Subscribers: machniak

Differential Revision: https://git.kolab.org/D290