Make test-strict append to $HGRCPATH, like other tests do since
61fcd9fac434.
Make tests append settings to $HGRCPATH instead of $HGTMP/.hgrc
and add documentation for this.
Clear contents of global hgrc for tests before running each test.
This fixes running test-mq-qdiff after test-mq, because of changed settings.
Add ui.strict config item.
This turns off command matching by unambiguous prefix, and is a good
thing if you want to write future-proof scripts.
This fixes issue 314.