Title: Trying to prevent read/write conflicts with a large user base
Level: 1
Component: wato
Version: 1.2.5i1
Date: 1386749884
Class: fix

When having a large amount of users, it might happen, that the user
configuration files are read while they are written e.g. by an automated
LDAP sync or some other modification to the user database. With bad
timing, the file could be read while being incomplete which might result
in syntax errors or similar unexpected situations. This changes the way
the files are being written to a more save way.
