dates: improve timezone handling
datestr:
- add format specifiers %1 and %2 for timezone hours and minutes
- remove timezone and timezone format options
- correctly find timezone hours and minutes for fractional and negative timezones
- update users
strdate:
- correctly find timezone hours and minutes for fractional and negative timezones
fetch: don't proceed if working directory is missing files (
issue988)
churn: show comitter email addresses unclipped (bug 1023)
Email addresses were being clipped at a hard-coded 20 chars. Measure
the length of all email addresses and accommodate the longest.