[Network] Remove dependencies on external storage account

[tjprescott]

In order to support Profiles, the following create commands need to be converted to use either SDK calls or dynamic template generation.

Template Based

• Application Gateway (PR [Network] Convert Load Balancer and App Gateway Create to Dynamic Templates #2668)
• Load Balancer (PR [Network] Convert Load Balancer and App Gateway Create to Dynamic Templates #2668)

SDK Based

• Express Route Circuit (PR [Network] Convert network creates to use SDK #2371)
• Local Gateway (PR [Network] Convert network creates to use SDK #2371)
• NIC (PR [Network] Convert network creates to use SDK #2371)
• NSG (PR [Network] Convert network creates to use SDK #2371)
• Public IP (PR [Network] Convert PublicIP Create to use SDK #2294)
• Traffic Manager Profile (PR [Network] Convert network creates to use SDK #2371)
• VNET (PR [Network] Convert VNet Create to use SDK #2269)
• VNET Gateway (PR [Network] Convert network creates to use SDK #2371)

[derekbekoe]

This item needs to be done as part of #2199