Add a ‘Generate Token’ Request/Action to the ArcGISOnlineConnector

This would simplify workspaces that make REST api calls and utilize the enhanced security of the ArcGIS Online web connection. Current methods to generate a token include:

1.      Use a HTTPCaller with a username and password in the upload body:

f=json&username<username>&password<password>&expiration=180&referer=https://<yourorganisation>.maps.arcgis.com

2.      Use a custom transformer that uses a PythonCaller: https://hub.safe.com/publishers/rbraggaar/transformers/arcgisonlinetokengetter