help: move help topics from mercurial/help.py to help/*.txt
The help topics are loaded on demand so we wont hit the disk unless we
really have to.
Some commands allow the user to specify a date, e.g.:
- backout, commit, import, tag: Specify the commit date.
- log, revert, update: Select revision(s) by date.
Many date formats are valid. Here are some examples::
"Wed Dec 6 13:18:29 2006" (local timezone assumed)
"Dec 6 13:18 -0600" (year assumed, time offset provided)
"Dec 6 13:18 UTC" (UTC and GMT are aliases for +0000)
"Dec 6" (midnight)
"13:18" (today assumed)
"3:39" (3:39AM assumed)
"3:39pm" (15:39)
"2006-12-06 13:18:29" (ISO 8601 format)
"2006-12-6 13:18"
"2006-12-6"
"12-6"
"12/6"
"12/6/6" (Dec 6 2006)
Lastly, there is Mercurial's internal format::
"1165432709 0" (Wed Dec 6 13:18:29 2006 UTC)
This is the internal representation format for dates. unixtime is
the number of seconds since the epoch (1970-01-01 00:00 UTC).
offset is the offset of the local timezone, in seconds west of UTC
(negative if the timezone is east of UTC).
The log command also accepts date ranges::
"<{datetime}" - at or before a given date/time
">{datetime}" - on or after a given date/time
"{datetime} to {datetime}" - a date range, inclusive
"-{days}" - within a given number of days of today