* key maps are now frozenset instead of dict objects
* FactsBase now includes utility functions for transforming json data structures
Tested on NXOS 7.3(0)D1(1)
* adds support for std network facts
* adds support for default facts subset
* adds support for config facts subset
* adds support for interface facts subset
* adds support for hardware facts subset
* maintains backwards capabilitity with 2.1 facts module
Tested on NXOS 7.3(0)D1(1)
