Publish move-core-types v0.0.4

[plafer]

Branch: testnet

I'm trying to build a StructTag, however I have no way to import the type, since all sui crates use the unpublished move-core-types v0.0.4 crates.

Publishing it would allow me to depend on it. Or, is the crate re-exported somewhere by one of the sui crates?

EDIT: Are we expected to have this in our Cargo.toml?

move-core-types = {git = "https://github.com/MystenLabs/sui", branch = "testnet"}