* Update wasm proposal support docs
Rename `--enable` flags to simply names and additionally replace module
linking with the component model.
* Fix a typo
This commit adds initial (gated) support for the multi-memory wasm
proposal. This was actually quite easy since almost all of wasmtime
already expected multi-memory to be implemented one day. The only real
substantive change is the `memory.copy` intrinsic changes, which now
accounts for the source/destination memories possibly being different.
