doc/: Do not lie about format.inputdate

Since aa682f7 (Rework command line argument handling, 2014-08-06), the
format.inputdate option is no longer honored when parsing dates in
non-interactive mode. Update the documentation accordingly.

Signed-off-by: Lukas Fleischer <calcurse@cryptocrack.de>

doc/calcurse.1.txt

@@ -88,16 +88,6 @@ today, tomorrow, and the day after tomorrow. The first form is equivalent to
 *-Q --filter-type cal --from <date>*, the second form is equivalent to *-Q
 --filter-type cal --days <num>*.
 +
-The  date  format  used  is  the  one  specified in the ``General options''
-menu.  Four formats are available:
-+
---
-  1. mm/dd/yyyy
-  2. dd/mm/yyyy
-  3. yyyy/mm/dd
-  4. yyyy-mm-dd
---
-+
 'Note:' as for the *-a* flag, the calendar  from which to  read  the
 appointments can be specified using the *-c* flag.