General Cargo.toml cleanup. (#529)

* General Cargo.toml cleanup.

 - Remove travis-ci attributes.
 - Remove "experimental" badges from actively-developed crates.
 - Reflow some long lines.
 - Use dependency features consistently.
 - Add readme attributes

* Update WASI to the latest trunk.

This notably adds a .gitignore file for the WASI directory.

crates/interface-types/Cargo.toml

@@ -3,10 +3,10 @@ name = "wasmtime-interface-types"
 version = "0.2.0"
 authors = ["The Wasmtime Project Developers"]
 description = "Support for wasm interface types with wasmtime"
+license = "Apache-2.0 WITH LLVM-exception"
 categories = ["wasm"]
 keywords = ["webassembly", "wasm"]
 repository = "https://github.com/CraneStation/wasmtime"
-license = "Apache-2.0 WITH LLVM-exception"
 readme = "README.md"
 edition = "2018"
 
@@ -18,3 +18,6 @@ wasmparser = { version = "0.39.2", default-features = false }
 wasm-webidl-bindings = "0.6"
 wasmtime-jit = { path = '../jit', default-features = false }
 wasmtime-runtime = { path = '../runtime', default-features = false }
+
+[badges]
+maintenance = { status = "actively-developed" }