tests: add timeouts, make run-tests.py clean up dead daemon processes test timeout feature is needed for test with python 2.5 beta. if test does not complete in time (30 seconds is default), it is killed. some times daemon process used in test can be alive after the test is killed by user or by timeout. tests now record daemon pids into $DAEMON_PIDS and run-tests.py kills all living daemons after every test. final little change is to add newline to end of pid file printed by "hg serve", else "cat hg.pid >> $DAEMON_FILES" gives garbage.

abort: impossible time zone offset: 4444444
transaction abort!
rollback completed
abort: invalid date: '1\t15.1'
transaction abort!
rollback completed
abort: invalid date: 'foo bar'
transaction abort!
rollback completed
abort: invalid date: ' 1 4444'
transaction abort!
rollback completed
abort: date exceeds 32 bits: 111111111111
transaction abort!
rollback completed
abort: No such file or directory: .../test/bar