Document removal of the "-N" command line option

This option was removed in 6b95f7b67d.
Update the usage message, the man page and the manual accordingly.

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

doc/calcurse.1.txt

@@ -42,7 +42,7 @@ Synopsis
 --------
 
 [verse]
-*calcurse* [*-h*|*-v*] [*-N*] [*-an*] [*-t*[num]] [*-c*<file> | *-D*<dir>]
+*calcurse* [*-h*|*-v*] [*-an*] [*-t*[num]] [*-c*<file> | *-D*<dir>]
          [*-i*<file>] [*-x*[format]] [*-d* <date>|<num>]
          [*-s*[date]] [*-r*[range]] [*-S* <regex>] [*--status*]
 
@@ -143,10 +143,6 @@ appointments can be specified using the *-c* flag.
 'Note:' the calendar from which to read the appointments can be specified using
 the *-c* flag.
 
-*-N*, *--note*::
-  When used with the *-a* or *-t* flag, also print note content if one is
-  associated with the displayed item.
-
 *-r*[num], *--range*[=num]::
   Print events and appointments for the 'num' number of days and exit. If no
   'num' is given, a range of 1 day is considered.
@@ -193,6 +189,9 @@ such as:
 $ calcurse --export > my_data.dat
 ----
 
+'Note:' The *-N* option has been removed in calcurse 3.0.0. See the 'FORMAT
+STRINGS' section on how to print note along with appointments and events.
+
 Format strings
 --------------