peepmatic: Introduce the peepmatic-fuzzing crate

This crate contains oracles, generators, and fuzz targets for use with fuzzing
engines (e.g. libFuzzer). This doesn't contain the actual
`libfuzzer_sys::fuzz_target!` definitions (those are in the `peepmatic-fuzz`
crate) but does those definitions are one liners calling out to functions
defined in this crate.

cranelift/peepmatic/crates/fuzzing/Cargo.toml

@@ -0,0 +1,22 @@
+[package]
+name = "peepmatic-fuzzing"
+version = "0.1.0"
+authors = ["Nick Fitzgerald <fitzgen@gmail.com>"]
+edition = "2018"
+publish = false
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+arbitrary = { version = "0.4.1", features = ["derive"] }
+bincode = "1.2.1"
+env_logger = "0.7.1"
+fst = "0.4.1"
+log = "0.4.8"
+peepmatic = { path = "../.." }
+peepmatic-automata = { path = "../automata", features = ["serde"] }
+peepmatic-runtime = { path = "../runtime", features = ["construct"] }
+peepmatic-test = { path = "../test" }
+rand = { version = "0.7.3", features = ["small_rng"] }
+serde = "1.0.106"
+wast = "13.0.0"