[oden] IO: Load Strings

It's useful. The stock JS way is bad.

src/io.ts

@@ -6,6 +6,12 @@ import * as core from "io-core";
  * @param path The path of the file to load.
  * @returns The contents of the file.
  */
-export function load(path: string): Promise<ArrayBuffer> {
-  return core.load(path);
-}
+export const load = core.load;
+
+/**
+ * Load the specified file into memory as a string.
+ *
+ * @param path The path of the file to load.
+ * @returns The contents of the file decoded from utf-8.
+ */
+export const load_string = core.load_string;