Splits the PubSub sample down into connect samples that only show how to make a connection.
* Split pubsub samples into smaller connect samples
* Added builder creation functions to command line utils and simplified pubsub sample
* Further simplification of existing samples
* Adjusted README to fit latest changes
* Adjusted code based on code review:
* Fixed websocket test passing region as the command instead of signing_region
* Adjusted WindowsCertPubSub to WindowsCertConnect. Modified to fit other connect samples
* Updated README to make command examples consistent