CLC improvements

[jjg-123]

• Add a low-level switchs, echo_http_request, that spits out exactly what is sent over the wire to the server, and echo_http_response for the raw response from the server. Writing a cUrl interface to OA4MP would be excruciating unless a developer could actually see what the requests were.
• Improve failure modes for load call. Right now it just says "error". It should, in line with the other methods, be more informative, such as "missing entry in config file". The machinery is there, just catch any exception and print out a summary.