Previously, all calls to the vSphere API assumed an instance variable called
`@connection`. This commit prepares the provider for a connection pooler:
- Removes all references to `@connection` where needed and funnels all calls to
get a vSphere connection through the newly renamed method `get_connection`.
For the moment, this still uses `@connection` behind the scenes but will make
it easier in the future to migrate to a connection pooler
- Removes all references and tests for the ensure_connected method as it's no
longer required
- All methods that explicitly need a connection object will have this as part of
the method parameters
- The connect_to_vsphere method has been changed so that instead of setting the
instance level `@connection` object it just returns the newly created connection.
This can then be easily consumed by a connection pooler later.
Previously, the vSphere Provider had two methods called
`find_least_used_compatible_host`: one in the base class and one in the vSphere
helper methods. This commit renames the vSphere helper methods and tests to
`find_least_used_vsphere_compatible_host` to stop the conflict.
This commit fixes minor rubocopy violations in eleven source files. Minor
violations are those that include formatting, single quotes, and recently added
classes.
