Add some list of the keyboard shortcut to the man page

man/viewnior.1

@@ -22,6 +22,51 @@ Show this help and exit
 .TP
 \fB\-\-version\fR
 Show version information and exit
+.SH KEYBOARD SHORTCUT
+.IP "Ctrl-o"
+Open an image
+.IP "Ctrl-f"
+Open a folder
+.IP "Ctrl-w, q"
+Close Viewnior
+.IP "Ctrl-s"
+Save changes
+.IP "Ctrl-r"
+Rotate image clockwise
+.IP "Ctrl-R"
+Rotate image anti clockwise
+.IP "Ctrl-F8"
+Set the selected image as the desktop background
+.IP "F5"
+Toggle slideshow
+.IP "F11"
+Toggle fullscreen
+.IP "Del"
+Delete the current file
+.IP "+, ="
+Zoom in
+.IP "-"
+Zoom out
+.IP "c"
+Crop image
+.IP "h"
+Flip horizontally
+.IP "v"
+Flip vertically
+.IP "Space, Right"
+Go to next image
+.IP "Backspace, Left"
+Go to previous image
+.IP "Alt-Home"
+Go to first image
+.IP "Alt-End"
+Go to last image
+.IP "Ctrl-0"
+Set image size to 100%
+.IP "0"
+Fit the image
+.IP "Alt-Return"
+Show info about the current file
 .SH "SEE ALSO"
 .PP
 Website: http://siyanpanayotov.com/project/viewnior/