add support for getting resources via relative urls
update http request functions, adding basic support for POST/PUT/DELETE
410 will get returned for deleted resources, treat the same as 404
update http post/put calls to sent a proper content-type. rework core fhir-request function to accept a request type and handle fhir error response parsing/returns
clean up response error handling
add create resource support. re-do request handling a bit to handle http 201 returns which include a "location" header
add doc-comment
add notes about exceptions being thrown to doc-comments
clean up some old comment out test code
add update resource function
fix following response "Location" headers to not just follow them with HTTP 201 responses
update doc comments
add some simple validation sanity checks on the create/update functions
add some more validation/sanity checks