Document ampm()

docs/WHATSNEW

@@ -27,6 +27,8 @@ CHANGES TO REMIND
 - IMPROVEMENT: If terminal size can be determined, set $FormWidth to
   terminal width - 8; if not, set $FormWidth to 72.
 
+- MINOR IMPROVEMENT: Add the "ampm()" built-in function.
+
 * Version 3.3 Patch 0 - 2020-01-31
 
 - FIX: rem2ps: Add a %%PageBoundingBox: document structuring convention

man/remind.1

@@ -2223,6 +2223,20 @@ is supplied, only the date component is used.
 Returns the time of "astronomical twilight" on the specified \fIdate\fR.  If
 \fIdate\fR is omitted, defaults to \fBtoday()\fR.
 .TP
+.B ampm(t_time [,s_am [,s_pm]])
+Returns a \fBSTRING\fR that is the result of converting \fItime\fR
+to "AM/PM" format.  The optional arguments \fIam\fR and \fIpm\fR are
+the strings to append in the AM and PM case, respectively; they default
+to "AM" and "PM".  For example:
+.RS
+.PP
+.nf
+        ampm(0:22)                 returns "12:22AM"
+        ampm(17:45, "am", "pm")    returns "5:45pm"
+.fi
+.PP
+.RE
+.TP
 .B args(s_fname)
 Returns the number of arguments expected by the user-defined function
 \fIfname\fR, or \-1 if no such user-defined function exists.  Note that