Rcparam ng proposal (don't merge)

As discussed very briefly in the last hangout, this a draft of the idea to use wrapped functions monkey-patched into the classes as a way to control the default value of any kwarg on any function.

The advantage here is that many of the entries in rcparameters can be eliminated and allows fine-grained control of each kwarg on each function

The down side is that this draft relies on closures.  Further, it is not immediately obvious to me how to deal with parameters shared across many functions (I think either automating setting them or setting them at a low enough level).

It is also not clear how this will work with the `style` module.

There is currently no validation.