The default behavior is to update_cache if changed.
If you add more then one repo, you may not want to update cache for every repo separately.
So you can now disable update_cache with this new option e.g. update_cache=no
Updating cache can also be handled using the apt module.
1. Debian Squeeze is supported out of box now.
2. Repository type "deb" or "deb-src" should be explicitly specified.
3. If a source had beed added it must be possible to remove it.
4. PPA can be only used against Ubuntu hosts.
Migrated all examples: in DOCUMENTATION=''' string to standalone EXAMPLES=''' string
Added deprecation warning to moduledev.rst and remove deprecated example from it
Fixed up a few typos and uppercased some acronyms.
add consistency to how EXAMPLES are formatted
