[Do Not Merge] Provide debugging file

[keefertaylor]

$ open ./XpringKit/Common/Resources/index.html

Then:

• command +option + j to open web tools in chrome
• functionality lives under XpringCommonJS in browser console

Here's an example command:

> XpringCommonJS.XrpUtils.isValidAddress("keefer")
< false

Things not working? You probably need to make some changes in xpring-common-js and then run the rebundle script:

cd xpring-common-js && <make changes, pull a new commit, etc> && cd ..
./scripts/bundle-js.sh
<refresh chrome>

NOTE: If you ever commit this file it gets bundled inside the SDK which we probably don't want to do. You could commit it and use an exclude in project.yml or you can just merge this PR into branches when you want to debug.