Correctly quote repo= when adding items

Because repository can be a string that includes spaces it needs to be
quoted to prevent ansible failing.
Add support for adding apt signing keys

This is basically a copy of apt_repositories but adjusted to handle
keys instead. It sits before repositories since it can't refresh on
its own but the keys need to be loaded before apt runs next.
Merge branch 'support-for-adding-new-keys-to-apt' of https://github.com/goetzk/ansible-apt into develop
added keys
Merge branch 'release/1.2.0'
added keys note
Configure apt (install template) before running any package affecting operations

Although its impact is generally minor, apt-get dist-upgrade does recognise
--no-install-recommends and acts accordingly. Since its assumed recommends
are not desirable at all the config is now installed before the ansible apt
dependencies ensuring it happens before all upgrades/installs/removals/etc.
Only remove packages if installs occur

This code change means package cleanup will only be run if packages
are installed or upgraded - the most likely reason for those files
to be out of date.

I've tested with no change and with a package install - both seemed
 to work correctly but its not a very comprehensive test.
Merge branch 'Configure-apt-before-updates' of https://github.com/goetzk/ansible-apt into develop
Merge branch 'release/1.2.1'
merged goetzk:Only-remove-packages-if-installs-occur
- cleanup only on changes, closes #4
Merge branch 'release/1.2.2'
Add variable to have apt mount root read write

In cases where you have a read only root filesystem a snippet like this is
required to ensure apt is able to run correctly.

Obviously if /usr is on another filesystem that would need a fragment too but I
don't have a setup like that to test with.
renamed files
Merge branch 'release/1.3.0'
added templates
Merge branch 'release/1.3.1'