Reapply "Add support for shebang with arguments"

This reverts commit 8c6309c3f5bd3ef8e0ff2a49ef83e998ba8319ec.

dosh

@@ -13,6 +13,17 @@ then
 	shift
 	set -- -s "$@"
 	exec "$0" "$@"
+elif [ "$__" != "/bin/bash" ] && [ "$__" = "$2" ]
+then
+	echo "Warning: Splitting the single shebang argument into many is not portable!" >&2
+	echo "         Please consider using env(1) and its split option -S instead:" >&2
+	echo "             #!/usr/bin/env -S dosh $*" >&2
+	read -r -a args <<<"$1"
+	shift
+	exec <"$1"
+	shift
+	set -- "${args[@]}" -s "$@"
+	exec "$0" "$@"
 fi
 
 set -e