…e var-args

The var-args in the middle of parameter lists for Model#start and Model#on make it difficult to write TypeScript type definitions for them.

These backwards-compatible changes add alternative signatures that don't use var-args.

1) Model#start now supports a new array format for input paths:

  model.start(outPath, inPath1, inPath2, ..., fn);  // Old
  model.start(outPath, [inPath1, inPath2, ...], fn); // New

2) Model#on now checks if the path pattern is a pre-split array, and if so, it calls the listener with a ____Event instance and the wildcard-captured segments as an array:

  model.on('change', 'foo.**', (captures..., value, previous, passed) => {});  // Old
  model.on('change', ['foo', '**'], (changeEvent, captures) => {});  // New

A ChangeEvent would look like {value, previous, passed}.

…nges