Make GSP-Field-Tags aware of Domain-Classes

This is a feature-request to enhance the functionality of Grails-Form-Tags (like <g:input ..>,<g:select ...> and so on).
The central idea is that the tags could take an additional bean- and property-parameter. In consequence the
field knows the constraints (e.g. field-size), knows if an error occurred and so on.

Marc Palmer's BeanTagLib (aka ModelTagLib) seems to be a perfect base for this.

Please check out: http://www.grails.org/Draft_ModelTagLib
And the little discussion at: http://www.nabble.com/Future-and-Status-of-the-ModelTagLib--td22163176.html