Feature/US749617 update for 10.1

[jchanbcbc]

Updated Ansible scripts to enable Gateway upgrades to 10.1.

• Ported changes from poc branch (minus the test configuration)
• Fix timeout issue with upgrade_gateway_database_schema.yml which occurs when updating large database which contains both otk and ssg db.
• Fix sample migration playbook to update getting the destination gateways from hosts.yml that uses the newer format.

Note: as noted by Jag, there is an issue with Ansible Lint which prevents it from running successfully.

[jagsgill]

looks good 👍
Ok to ignore the linter issue. It appears be broken at the moment because it pulls the latest version of ansible-lint python module and there is a dependency issue there.