Remove the prefix option; pick name from PWD

Too complicated and little useful

src/libexec/saturnin-ln

 esac done
 
 test -z "$target"               && target=$(load target)
-test -z "$prefix"               && prefix=$(load prefix)
 test -z "$target"               && target=$DEFAULT_TARGET
-
-case $prefix.$name in
-    .)          die "provide at least name or set prefix in ln.conf";;
-    $prefix.)   name=$prefix;;
-    .$name)     :;;
-    *)          name=$prefix.$name;;
-esac
+test -z "$name"                 && name="$(basename "$PWD")"
 
 debug -v name target