8.2 OpenAUC connotation of simple vs. complex

The libxmlrpc_client++ shows what is meant there by a simple or complex client. We alter this as follows.

By ``complex'' we mean a client where the MD API are used to perform the maintenance of state on observables.

By ``simple'' we mean a high level representation of observable frames where the client program references the frame as a data structure reading and writing variable values and the client manages the client-server interaction.

The simple interface is thus actually the more complex one from the point of view of the implementation of this project and the UDP based layer which the design calls and which was implemented after the equivalent XMLRPC based operation (which is available in the sources for custom client development) was verified. However, it will be a powerful element for the project overall as it will allow new MD clients to be brought into operation very quickly.

It is not intended that this simple interface would be for anything other than maintaining an overall coherent state of a set of shared observables with minimal effort. Any active interaction with the MD system such as issuing and responding to commands and the like will require the use of the complex interface.