* ACI: Various changes to module documentation and guide
This PR includes:
- We moved the object class information to the notes
- Add version information to guide chapters
- Add generic note to modules with reference to ACI guide
- Reference known issues in aci_rest documentation
- Remove module_utils function docs from modules
- Indicate which parameters are not required for querying all objects
- Added missing RETURN information
* Fix copyright strings
* Remove aci_domain_to_encap_pool.py for v2.5
* More updates
* PEP8 fix
* Improve listings of parameters/return values
When ACI modules are being used for querying MOs, we should not return
the previous state, as there is no previous state, there's only the
current state.
This impacts a lot of tests that were used to testing the current state
as 'previous'.
