As a developer, I want to customize requests made with a REST Cient when I use it, so that I can accomplish my work easily without changing a REST client. 

In the current REST client, one defines specific java methods on the client, which can take specific properties. Only these defined methods are available to the consumers. However we want something more flexible that allows any code in the system to use the clients and take advantage of the credentials, token, url, etc that are configured on them. So it should be possible for a consumer to use those stored configurations, but dynamically supply any of their own needed options, like querystring parameters or headers.

Example:

From a template, I want to request a set of flights from an airport webservice: flights departing between two times, stored by airline. To do this I can use the configured Airport Rest Cient, and supply a custom querystring with the filter and ordering information.

Acceptance Criteria:

• Supply custom request VERB
• Supply custom request Querystring
• Supply custom request Body
• Supply a custom URL segment
• Supply custom headers.

TODO: This ticket needs to be updated by PM based on the current state.