Removed dropped slideshow mappings from man page & README

README.md

@@ -125,11 +125,6 @@ The following additional key commands are available in *image mode*:
     <,>          Rotate image (counter-)clockwise by 90 degrees
     \,|          Flip image horizontally/vertically
 
-    s            Toggle slideshow
-    Ctrl-'-'     Decrease slideshow delay
-    Ctrl-'+'     Increase slideshow delay
-    Ctrl-'='     Reset slideshow delay, or set it to [count] seconds
-
     a            Toggle anti-aliasing
     W            Resize window to fit image
 

sxiv.1

@@ -256,21 +256,6 @@ Flip image horizontally.
 .TP
 .B |
 Flip image vertically.
-.SS Slideshow
-.TP
-.B s
-Toggle slideshow.
-.TP
-.B Ctrl\-'\-'
-Decrease slideshow delay.
-.TP
-.B Ctrl-'+'
-Increase slideshow delay.
-.TP
-.B Ctrl-'='
-Reset slideshow delay to default value, or set it to
-.I count
-seconds.
 .SS Miscellaneous
 .TP
 .B a