test-parse-date: defines explicit start/end dates for DST
Prior to this patch, DST times where tested by specifying a custom TZ
environment variable that didn't defined DST transition times.
Due to a bug in glibc, the test fail on 32bits platforms that use timezone
files generated by zic from tzcode >= 2014c (glibc >= 2.20).
See https://sourceware.org/bugzilla/show_bug.cgi?id=19738
By defining explicit transition times for DST in the TZ environment variable,
the test is now independant to how the system guess those transition times.
$ hg init
$ touch unknown
$ touch a
$ hg add a
$ hg ci -m "1"
$ touch b
$ hg add b
$ hg ci -m "2"
Should show unknown
$ hg status
? unknown
$ hg revert -r 0 --all
removing b
Should show unknown and b removed
$ hg status
R b
? unknown
Should show a and unknown
$ ls
a
unknown