Add conf/quads.yml option to accomodate accessing switch via mgmt

[sadsfae]

In other R&D environments like ALIAS some folks may not have direct ssh access to their switch setup and instead go through the management interface.

This issue should cover any manual adjustments that were made on the 1.0.2 ALIAS Lab setup performed by @kambiz-aghaiepour and others to make sure it's included in the 1.1.0 codebase going forward.

Suggestion here, an access method conf file setting like switch_access_method: and an empty value or direct is the default (as it works now) but a value of switch_access_method: mgmt would include any necessary changes for changing command mode due to a different access method.