fixes #17 easier way to edit data-binded properties

added properties to Node prototyp
made it more fluent

eg: $0.editVM.value("test") when there is a dom node like <input
data-bind="value: itemToAdd">
added editBinding, edit$data, edit$root to window + feature switch

refactored method in function and called to string (cleaner)
extra option setting for edit methods (feature flag)
upgrade version number in manifest to 2.6.0

new feature (but behind default false option): edit methods