Knockout.js Binding: Fixing the initialization of the selected items in the multi-select

Fixing the initialization of the selected items in the multi-select for Knockout.js binding integration.  Currently a persisted binding value isn't being initialized correctly when using KO.  Instead the selectedOptions are only being set on during the update binding function or when the observableArray is changed.  With this fix, if the observableArray has initial values, they are selected as necessary.s