rust/pact_consumer API overhaul

At this point, I've touched almost every single line of code, so it's
probably a good idea to up...

This code may be discovered by people using crates.io or docs.rs, and so
we want to provide a br...

This is useful to get the matching semantics you normally want with
`each_like!` if you're using...

This is the value that everybody should be using, really, so let's make
this the default helper ...

This requires some pretty hairy Rust macro expansion, but it seems to
work nicely. The decision ...

The JavaScript versions of these names are shorter, and in particular,
the name `each_like` is m...

It appears that most JSON path engines accept identifiers with
underscores. (For an example, see...

This makes the API a bit nicer to use in practice, though I imagine
we'll want to fill in more v...

All of this polishing is based on various real-world experimentation,
trying to make this API as...

This makes matching much cleaner, syntactically.

Formerly, we used `JsonPattern` to represent values that were actually
strings. This allow the u...

This is analogous the `JsonPattern`, but it only works with strings.
We'll apply this to things ...

We provide:

1. New, modular builder types.
2. A new mock server wrapper that validates interact...

This isn't used anywhere in `pact_consumer`, and the compiler now warns
about that.

Let's use a directory structure that makes it easier to add XML later.

We also add support for generating JSON Path expressions from
`Matchable`s.

This code acts as a wrapper around `serde_json::Value`, but with support
for `JsonPattern::Term`...

It looks like every call site in both the `pact-reference` repo and in
our internal code at Fara...

Here, I use a two-pronged strategy:

1. Use much more flexible (but complicated) iterator constr...

The `s!` macro isn't fully idiomatic Rust. A more natural way of
handling these cases is to buil...

This is necessary to use the `pact_consumer` API, so let's just
re-export it. We'll add any othe...

The original version of this test was wrapped in `#[test]`, which meant
that the code was almost...

This syntax will use `path` when run locally, but `version` when
published to crates.io. (Also, ...

Several of the unit tests were broken, either by (1) updates to how
cargo works, or (2) the prev...

This allows us to share build artifacts between all of our Rust crates,
vastly speeding up compi...

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