test-run-tests.t: add extra data to tests for keyword tests

This adds a fair amount of overall instability in the enclosing .t. As
such, this is performed in its own commit, and a test for --keyword on
run-tests.t will be added in a followup change.
test-run-tests.t: add tests for skips

This will make some minor behavior changes in a future patch more obvious.
run-tests: fix test result counts with --keyword specified or skips occurring

This preserves the current behavior that excludes ignored or skipped
tests from the number of tests run, except when tests are ignored due
to the --retest flag.
log: allow patterns with -f

It's not uncommon for a user to want to run log with a pattern or directory name
on the history of their current commit.  Currently we prevent that, but
I can't think of any reason to continue blocking that.

This commit removes the restriction and allows 'hg log -f <dir/pat>'