Tweaks to get caching fully functional.

[peebles]

1. getCacheByHref() still incorrect, missing this case:
   https://api.stormpath.com/v1/applications/6fr66lFwpF8NTmFH0kITot/groups
2. Add recursive CacheHandler::get()
3. Recursive CacheHandler::put() was not storing the toplevel resource in
   some cases.
4. If process.env.NODE_DEBUG_SP=1, then print some debug statements when Stormpath
   fetches from cloud uri verses from cache. Also stores to cache are displayed.

[peebles]

I see its failing lint checks, although it seems like the checks are pretty strict. If there was a lint "script" in package.json, I could run it and fix the lint errors, but as it I wouldn't know how you are running lint. Let me know if you want me to do anything to help.

I noticed the npm module from doing a "npm install storm" is pretty far behind master...

[peebles]

I found that running "npm run test" ran lint. I fixed the lint errors.

[robertjd]

Hi @peebles, thanks for this pull request. We've been busy with other features, but we will definitely review this as soon as possible.