Make ncm-network depend on bridge-utils

We need very often brctl, and on minimal installations we may forget
about it.
Enhance the validation.
Configure the length of the key.
fix 2 small issue
node_desc should be literal, add test
update optiosn regexp 

This is the regexp created by James we use at RAL to match our nagios related sudo configuration. It has been used since February 2012. The new options are supported in SL5 onwards.
Untabify versionlock method
Don't versionlock packages whose version is a *.
update options regexp

Fixed regexp provided by James.
Refactor versionlock

It was getting too long, with too many comments, and there are some
intrusive changes in the pipeline.
Added new options

Added new sudo options as provided by James.
Test the new sudoers options.

They should get the correct amount of semicolons.
current production code
replace double comment hash
align with current production
use proper backup suffixes (all timestamped)
add basic test case
fix remarks
refactor move_slapdd code
Add unit tests for the locked_all_packages method.