Move the wasmtime crate directories form lib/* to wasmtime-*.

This follows a similar change to Cranelift made here:

https://github.com/CraneStation/cranelift/pull/660

wasmtime-runtime/Cargo.toml

@@ -0,0 +1,43 @@
+[package]
+name = "wasmtime-runtime"
+version = "0.1.0"
+authors = ["The Wasmtime Project Developers"]
+publish = false
+description = "Runtime library support for Wasmtime"
+categories = ["wasm"]
+keywords = ["webassembly", "wasm"]
+repository = "https://github.com/CraneStation/wasmtime"
+license = "Apache-2.0 WITH LLVM-exception"
+readme = "README.md"
+edition = "2018"
+
+[dependencies]
+cranelift-codegen = "0.29.0"
+cranelift-entity = "0.29.0"
+cranelift-wasm = "0.29.0"
+wasmtime-environ = { path = "../wasmtime-environ", default-features = false }
+region = "2.0.0"
+lazy_static = "1.2.0"
+libc = { version = "0.2.44", default-features = false }
+errno = "0.2.4"
+memoffset = "0.2.1"
+cast = { version = "0.2.2", default-features = false }
+failure = { version = "0.1.3", default-features = false }
+failure_derive = { version = "0.1.3", default-features = false }
+indexmap = "1.0.2"
+
+[target.'cfg(target_os = "windows")'.dependencies]
+winapi = { version = "0.3.6", features = ["winbase", "memoryapi"] }
+
+[build-dependencies]
+cmake = "0.1.35"
+bindgen = "0.47.1"
+regex = "1.0.6"
+
+[features]
+default = ["std"]
+std = ["cranelift-codegen/std", "cranelift-wasm/std", "wasmtime-environ/std"]
+
+[badges]
+maintenance = { status = "experimental" }
+travis-ci = { repository = "CraneStation/wasmtime" }