New module [ufw]: this module handles Ubuntu UFW operations
* Updated documentation related to IPv6 usage.

BugFixes:
* Solved the default_policy and state mutual exclusive status.
* Fixed changed status for IPv6 addresses.
Added @otnateos patch.
Separate state and policy parameters and cleanup implementation.
Cleanup and make 'app' and 'port' parameters mutually exclusive.
Fix python path.
Support for 'direction' ('in','out') and 'interface' (e.g. 'eth0')
Fix comment typos.