Improve oauthtoken

[adonisgarciac]

What does this PR do?

This PR try to improve the managment of oauthtoken for filetree_create, filetree_read and object_diff roles and some other fixes which they were seen during tests:

1. oauthtoken var is renamed because follow naming of the rest of roles: oauthtoken -> controller_oauthtoken
2. Control if controller_oauthtoken is given, the roles will not create the oauth token
3. If oauth token is created, it will be deleted at the end.
4. Remove generate token in filetree_read because this role only is to read variable definitions.
5. Add check what collection ansible.controller or ansible.awx is installed for object_diff role
6. fix controller_object_diff.py: it was I was handling credential_type as it would have organization.

How should this be tested?

Launch test playbooks for filetree_create, filetree_read and object_diff roles.

Is there a relevant Issue open for this?

N/A

Other Relevant info, PRs, etc

I think that, after this PR will be merged, I should generate a new release version because we have a lot of new features and fixes and we already have customers testing CasC using these roles.

[silvinux]

LGTM. Awesome job!.

[djdanielsson]

LGTM