Small improvements on binding syntax check, watching and API
* Report appropriate "access nil pointer" error instead of throwing
"symbol not found all the time"
* It's now possible to manually trigger watchers for an object
* Enforce embeding of PageCtrl - now renamed to BaseScope to page models
New binding code. Mega update with changes and fixes and improvements in code, structure and API.
* Better custom elements file structure and API
* Customelems now has an Update method which allows it to update along
with any changes to the bound symbols
* New binding algorithm which is much simpler and works better, solving
a previous problem that makes implementing updatable custom elem
impossible
* Some revamp in the architecture of bind
* Updates on tests, add more coverage and add new If binder test
* Small updates on the dom API