RPCs hiding heuristics using Strings

The whole issue of RPCs in SFC needs at somepoint to be addressed.

During introduction of Types (RspName, SfName etc) during a patch, I found that many RPCs are using the fact that things used to be Strings to allow various fields to be used interchangeably.

This isn't always WRONG but it does embed some implicit heuristics as to what various things mean (ie why is an RSPNAME and SFPNAME able to be used interchangeably? If so then perhaps they should be the same defined type, if not then ... etc.. you get the idea. So rather than decorating the code with long comments or obscure comments, as I refactor for typedefs I am going to put a TODO with this BugID so we can track them.