Code review comment for lp:~altair-ibn-la-ahad/ubuntu/precise/update-notifier/bug-887650

First, thanks a bunch for working on this, its a very nice fix and will improvethe usability quite a bit.

Some remarks:
- I would also prefer a MP against lp:update-notifier
- I personally prefer $(command) over `command`

Instead of:
  if [ `echo "$THIS_VERSION < $VERSION_ON_CD" | bc` -eq 1 ]; then
you can use:
  if dpkg --compare-versions "$THIS_VERSION" lt "$VERSION_ON_CD"; then
...

This will work as the version number semantic of a ubuntu/debian package is a superset of the version
numbers of the ubuntu distribution releases and I think its slightly more readable this way.

It would be great if you could tweak the MP to address these small issues and I will be happy to merge
and upload then!