Update wasm-tools crates (#4246)

This commit updates the wasm-tools family of crates, notably pulling in
the refactorings and updates from bytecodealliance/wasm-tools#621 for
the latest iteration of the component model. This commit additionally
updates all support for the component model for these changes, notably:

* Many bits and pieces of type information was refactored. Many
  `FooTypeIndex` namings are now `TypeFooIndex`. Additionally there is
  now `TypeIndex` as well as `ComponentTypeIndex` for the two type index
  spaces in a component.

* A number of new sections are now processed to handle the core and
  component variants.

* Internal maps were split such as the `funcs` map into
  `component_funcs` and `funcs` (same for `instances`).

* Canonical options are now processed individually instead of one bulk
  `into` definition.

Overall this was not a major update to the internals of handling the
component model in Wasmtime. Instead this was mostly a surface-level
refactoring to make sure that everything lines up with the new binary
format for components.

* All text syntax used in tests was updated to the new syntax.

Cargo.toml

@@ -52,13 +52,13 @@ test-programs = { path = "crates/test-programs" }
 wasmtime-runtime = { path = "crates/runtime" }
 tokio = { version = "1.8.0", features = ["rt", "time", "macros", "rt-multi-thread"] }
 tracing-subscriber = "0.3.1"
-wast = "41.0.0"
+wast = "42.0.0"
 criterion = "0.3.4"
 num_cpus = "1.13.0"
 winapi = { version = "0.3.9", features = ['memoryapi'] }
 memchr = "2.4"
 async-trait = "0.1"
-wat = "1.0.42"
+wat = "1.0.43"
 once_cell = "1.9.0"
 rayon = "1.5.0"