[Framework] Continue implementing fundamentals

Continue implementing classes which represent fundamental
concepts within the framework layer. WTD-518.

In particular, add methods which will be useful during the
extension resolution phase of framework start up.

platform/framework/src/Constants.js

@@ -6,5 +6,12 @@
 define({
     MODULE_NAME: "OpenMCTWeb",
     BUNDLE_LISTING_FILE: "bundles.json",
-    BUNDLE_FILE: "bundle.json"
+    BUNDLE_FILE: "bundle.json",
+    SEPARATOR: "/",
+    DEFAULT_BUNDLE: {
+        "sources": "src",
+        "resources": "res",
+        "test": "test",
+        "extensions": {}
+    }
 });