As demonstrated by http://xkcd.com/936/

 the current password policy encourages
passwords with low entropy. Young users especially struggle with the password
policy. This patch drops the mandatory number & 2 letters rule.

Change-Id: Ifb9f4a24f53ab86ddf52f69ca3e07611c41bec64
Signed-off-by: Melissa Draper <melissa@catalyst.net.nz>