Track method changes in the kernel registry.

References #1662.
Replace `jQuery.each` with `Object.keys` to remove dependency on jQuery.
Only call `model.callingMethod` until the first driver returns a result.
Remove the unneeded `methodValue` parameter from `model.callingMethod`.
Define `kernel.setMethod` and `kernel.getMethod`.
New utility functions to convert between Handlers and functions.
Implement `settingMethod`/ `gettingMethod`; send changes through the kernel.
Replicate method changes.
Detect spacing to retain round-trip formatting in most cases.