Trap
* Remove unsafety from `Trap` API This commit removes the `unsafe impl Send` for `Trap` by removing the internal `HostRef` and leaving `HostRef` entirely as an implementation detail of the C API. cc #708 * Run rustfmt
Groups all CL data structures into single dependency to be used accross wasmtime project.
* Record original Trap from API callback. Fixes #645 * use TrapRegistry * comment about magic number