revset: ensure we are reversing a list (issue3530)

test-keyword: adapt for Windows

tests: don't use dates before epoch in test-keyword.t Timezone offsets of less than a minute is not shown but can cause displayed dates to be before epoch start - and dates before epoch start is not shown correctly on Windows (see also 4d5b12a5517b). These 'negative' dates could be considered undefined behaviour so we don't care and swap the tests values for timestamp and timezone.

tests: make test-convert-bzr.t more stable The test would occasionally fail because datesort don't have sub-second granularity and thus can't sort commits made in the same second. The test is made more stable by adding 1 second of sleep to make sure the bzr commits are done with different timestamps.

casecollision: add tests Add more tests to exercise the case collion detection code

dirstate: add dir/file collision test Add a test exercising collisions in add between files and directories of the same name.