[x] Refactor the _get_parser() method so that sub-parser creation can mostly be done by a function call
[x] Do sub-parsers for all Rust libraries that are consistent with each other
[x] Add --no-publish option for all Rust libraries that were chosen in the previous step
[x] Then, merge treatment of devicemapper library in with the other Rust libraries
[x] Merge handling of stratisd with other Rust crates
[x] Remove useless trampoline functions
[x] Try out subcommand aliasing in order to have more predictable, or just shorter subcommand names
[x] Might want to stop suppressing backtrace printing (optional)
[x] Python library releasing:
[x] Set up a PythonPackages class analogous to the RustCrates class and relocate the tag_python_library method to it. Fix up call sites as necessary.
[x] Add a set_up_subcommand method to the PythonPackages class and call where appropriate.
[x] Support a "--dry-run" option for Python packages.
[x] Add an entry for hs-dbus-signature, apparently we've never released it since this script came into being
[x] See if we can handle testing repo along with the other Python packages. It's got a different command-line, and fewer actions, but maybe something can be done there.
[x] Move _publish() into RustCrates, it's not used anywhere outside it. Make it a static method.
_publish()into RustCrates, it's not used anywhere outside it. Make it a static method.