upgrade: add '-' in optimization name
The older name `redeltaall` was hard to type and read. The newer form should
be more user-friendly.
We keep backward compatibility with the old form (at least for a while).
Having to use different form depending on the version is very impractical and
error prone.
#
# Avoid interference from actual test env:
unset HGTEST_JOBS
unset HGTEST_TIMEOUT
unset HGTEST_PORT
unset HGTEST_SHELL