In preparation for releasing `internals v0.4.0` bump the version number,
add a changelog entry, update the lock files, and depend on the new
version in all crates that depend on `internals`.
In preparation for release bump the version and add a changelog entry.
Includes updating the dependency in `bitcoin` and `hashes` as well as
the minimal/recent lock files.
Tobin C. Harding
Andrew Poelstra