Bug #13, Buster.js unit tests do NOT work on Internet Explorer, so

* Add conditional comments so that tests aren't run! (They crash MSIE)
* Add a "Sorry.." message for MSIE
Bug #15, Security - filter un-safe attributes and value-types

* Add a Regex match against an attribute 'whitelist' - `ATTR_SECURE`
* Add a typeof test for the value
* Add unit tests - issue #13