applied Martti Kühne's dmenu monitor patch

f6581ca966/monarg.patch becomes upstream now

dmenu.1

@@ -7,6 +7,8 @@ dmenu \- dynamic menu
 .RB [ \-f ]
 .RB [ \-i ]
 .RB [ \-l
+.RB [ \-m
+.IR monitor ]
 .IR lines ]
 .RB [ \-p
 .IR prompt ]
@@ -49,6 +51,9 @@ dmenu matches menu items case insensitively.
 .BI \-l " lines"
 dmenu lists items vertically, with the given number of lines.
 .TP
+.BI \-m " monitor"
+dmenu is displayed on the monitor supplied.
+.TP
 .BI \-p " prompt"
 defines the prompt to be displayed to the left of the input field.
 .TP