Merged the functionality of gitsch2ppm into schhist2web.

- scripts/normalizeschps: don't edit in place and thus become capable of
  running in a pipe
- scripts/schps2ppm: considered - to be an option and thus didn't accept
  it as input file name
- scripts/schhist2web: open-coded functionality of "gitsch2ppm"
- scripts/gitsch2ppm: removed

scripts/schps2ppm

@@ -31,10 +31,9 @@ while true; do
     -r)	[ -z "$2" ] && usage
 	RES="$2"
 	shift 2;;
-    -*)
-	usage;;
-    *)
-	break;;
+    -)	break;;
+    -*) usage;;
+    *)	break;;
     esac
 done