Binder Priorities

This pull request adds support for an optional `binder.priority` property, which will determine the bind order of the bindings within a view (highest will bind first).

Default binder priorities are the following:

- **3000**: blocking binders (`if`, `unless`, `each-*`)
- **2000**: two-way binders (`value`, `checked`, `unchecked`)
- **1000**: function / event handler binders (`on-*`)
- **0**: everything else

#409, #410