Validation currently depends on 'ready' event regardless of 'ajax' setting

[brettz9]

The README says:

*Note If the ajax property is true and JSON Editor needs to fetch an external url, the api methods won't be available immediately.
Listen for the ready event before calling them.

editor.on('ready',function() {
  // Now the api methods will be available
  editor.validate();
});

However, at least in Firefox, this pattern is also required regardless of whether ajax is true.

(This is because requestAnimationFrame acts asynchronously to set self.validation_results and validation_results will not yet have been set if editor.validate() is called immediately after the editor instantiation.)

I didn't know if you wanted the README to clarify this or if you want to avoid the asynchronicity for non-Ajax JSON validation.

Also, as an aside (and I'll start a new issue for it if you are open to it), it would be awesome if we could optionally support $ref JSON references within normal JSON files in addition to use within JSON Schema: http://tools.ietf.org/id/draft-pbryan-zyp-json-ref-03.html

[jdorn]

I think I broke this when I fixed a bug with error messages not showing up - f48d53a#diff-a8b71adb8094d5cdb63026cc0b85ddcfL181

It should be easy enough to fix this by running validation during initialization like before and again in requestAnimationFrame.