Initial reorg.

This is largely the same as #305, but updated for the current tree.

crates/api/src/lib.rs

@@ -0,0 +1,35 @@
+//! Wasmtime embed API. Based on wasm-c-api.
+
+#![cfg_attr(not(feature = "std"), no_std)]
+
+mod callable;
+mod context;
+mod externals;
+mod instance;
+mod module;
+mod r#ref;
+mod runtime;
+mod trampoline;
+mod trap;
+mod types;
+mod values;
+
+pub mod wasm;
+
+#[macro_use]
+extern crate alloc;
+
+pub use crate::callable::Callable;
+pub use crate::externals::*;
+pub use crate::instance::Instance;
+pub use crate::module::Module;
+pub use crate::r#ref::{AnyRef, HostInfo, HostRef};
+pub use crate::runtime::{Config, Engine, Store};
+pub use crate::trap::Trap;
+pub use crate::types::*;
+pub use crate::values::*;
+
+#[cfg(not(feature = "std"))]
+use hashbrown::{hash_map, HashMap, HashSet};
+#[cfg(feature = "std")]
+use std::collections::{hash_map, HashMap, HashSet};