Enable Azure Cloud Environments in Metrics

As of Aug 2019, there are 4 Azure Cloud environments with distinct endpoints around the world:

1. Azure Public Cloud
2. Azure Gov Cloud
3. Azure China Cloud
4. Azure Germany Cloud

This release enables selection of the cloud that you're operating in, enabling the add-on to communicate with resources like key vaults and the ARM api.

New Resource Types

Recent resource type additions to Azure Monitor have a slightly different schema which broke the code. Also added a few log categories to the json. Also tested metrics via event hubs. This works nicely.

Bug fix release

This release fixes the "Cannot read property 'write' of null" error. It also moves SPL packages to the releases section of the repo.