UILoader module and FormBase class implemented.

__Spec:__ https://www.dropbox.com/s/uqeuui8gzpka49n/UI%20Specification%20for%20Authoring%20Tool%2004.22.docx

__Code Review:__ http://mrccodereview.cloudapp.net/ui#review:id=1110

Includes:

1. Implementation of FormBase and UILoader described in spec.
2. Implemented style for form base.
3. Example of form.
4. Minor fixes.