rust: using policy.importrust from Python callers...
rust: using policy.importrust from Python callers
This commit converts all current Python callers of
mercurial.rustext to the new policy.importrust system.
After this point, going through policy.importrust
or policy.importmod (in some more distant future)
is mandatory for callers of Rust code outside of
Python tests.
We felt it to be appropriate to keep Rust-specific tests
run inconditionally if the Rust extensions are present.