Azurerm

- list_nsgs(access_token, subscription_id, resource_group)
- list_nsgs_all(access_token, subscription_id)
- list_asgs(access_token, subscription_id, resource_group)
- list_asgs_all(access_token, subscription_id)

- Fix to graph functions (incorrect GRAPH_RESOURCE_HOST value)

- Fix to graph functions (required import os library)

- Added Microsoft Graph functions:
get_graph_token_from_msi(), get_object_id_from_graph()
- A user's object ID is required when creating an Azure Key Vault for example.
- get_graph_token_from_msi() assumes you're running in an Azure Cloud Shell or VM.

- Added list_tenants() to list tenants user has access to. Added test and updated
subscriptions_test.py. Updated BASE_API version.
- Added key vault functions: create_keyvault(), delete_keyvault(), get_keyvault(),
list_keyvaults(), list_keyvaults_sub(). Added keyvault unit tests.

- Update get_access_token_from_cli() to work in Azure cloud shell by getting token from MSI
endpoint