Improve internal route and parameter parsing

[bakerkretzmar]

This PR rewrites most of Ziggy's JavaScript core with two main goals:

1. Take advantage of the bindings property added in Add full support for implicit route model binding #315 to more reliably handle complex nested parameters and route model binding.
2. Don't mutate Ziggy's own internal state while it's parsing/compiling a URL—we used to delete properties from this.urlParams as we handled them, which constrained the order they could be handled in and caused other headaches.

To accomplish this, several things are now handled quite differently internally:

• Parameters are immediately parsed into an object, with parameter names as keys and plain strings or integers as values. This makes merging in default parameter values and compiling the final URL much simpler.
• Route template 'segments' are parsed into an ordered array of objects, which makes them easier to access repeatedly and to perform merge-like operations on with their parameter values.
• There is a new Route class that encapsulates functionality related to handling one specific route, as opposed to some or all of them.

This PR also adds one hot new feature: the ability to pass a second argument to current() with an object containing parameters to check in addition to the route name. If that sounds familiar it's because I copied and pasted that sentence from #314, which also added that feature, but this time I didn't half-ass it and so the caveat in that PR no longer applies—now, the object passed to current() will be partially matched against the current URL, so you can pass a subset of parameters and only the ones you pass will be checked. This PR therefore closes #314 and closes #211.

This PR removes:

• the publicly available name, absolute, ziggy, urlBuilder, template, urlParams, queryParams, and hydrated properties on the Router class
• the publicly available normalizeParams(), hydrateUrl(), matchUrl(), constructQuery(), extractParams(), parse(), and trimParam() methods on the Router class

And deprecates:

• with() in favour of just passing parameters to the route() function
• check() in favour of has() for consistency with Laravel

And uses microbundle's property mangling to restrict internal APIs.

Yes, that's a lot to remove. None of these APIs were documented, and most of them were only used or intended to be used internally. Removing them and replacing their functionality with internal properties and methods (hidden by mangling them as described above) gives us a lot more flexibility to tweak their implementation later and makes Ziggy's intended uses and what its public APIs are much clearer. Most of the functionality of the removed methods that do more than simple string parsing is still available in other ways, and most of the information contained in the removed properties is available already in the global Ziggy configuration object.

Todos before merging:

• Update Changelog

[mattstauffer]

Freaking fantastic work