Switch to side-by-side view

--- a/src/sampleconf/mimeview
+++ b/src/sampleconf/mimeview
@@ -124,6 +124,7 @@
 application/x-rar = ark %f
 application/x-tar = ark %f
 application/zip = ark %f
+application/x-7z-compressed = ark %f
 
 application/x-awk = emacsclient --no-wait %f
 application/x-perl = emacsclient --no-wait %f