Merge branch 'jk/tzoffset-fix' into maint

The internal code used to show local timezone offset is not prepared to handle timestamps beyond year 2100, and gave a bogus offset value to the caller. Use a more benign looking +0000 instead and let "git log" going in such a case, instead of aborting. * jk/tzoffset-fix: local_tzoffset: detect errors from tm_to_time_t t0006: test various date formats t0006: rename test-date's "show" to "relative"