Static provider setting middleware.
Simple address prefix-matching provider setting middleware
Add some address normalization to prefix-based provider middleware.
Merge branch 'develop' into feature/issue-869-provider-setting-middleware
Rename get_prefix() to get_provider(), which is much more sensible.
Cleaner provider_prefixes setup.
Set provider values on outbound messages.
Add notes on ordering of middleware.
Mention possible need to sandwich middleware.
Merge branch 'feature/issue-869-provider-setting-middleware' into develop
Merge branch 'develop' into feature/issue-864-message-store-compound-index