adding latex standard to ranger

.config/ranger/rifle.conf

@@ -101,6 +101,7 @@ mime ^video, terminal, !X, env VIDEO       = "$VIDEO" -- "$@"
 ext pdf, env READER,   X, flag f = "$READER" -- "$@"
 ext djvu, env READER ,X, flag f = "$READER" -- "$@"
 ext csv|xls|xlsx, env TABLE, X, flag f = "$TABLE" -- "$@"
+ext tex, env LATEX, X, flag f = "$LATEX" -- "$@"
 
 #-------------------------------------------
 # Image Viewing: