Add node modules and compiled JavaScript from main (#172)

Co-authored-by: Oliver King <oking3@uncc.edu>

node_modules/underscore/modules/extendOwn.js

@@ -0,0 +1,7 @@
+import createAssigner from './_createAssigner.js';
+import keys from './keys.js';
+
+// Assigns a given object with all the own properties in the passed-in
+// object(s).
+// (https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object/assign)
+export default createAssigner(keys);