Fix usage patterns

libexec/saturnin-clip

 STORAGE_DIR="$HOME/.local/share/saturnin/clips"
 
 usage() {
+    usage_is "[ls]"
     usage_is "save [-1|-2|-c]"
-    usage_is "load [-1|-2|-c] name"
+    usage_is "load [-1|-2|-c]"
 }
 
 clipln() {