[PRD-3687] Reports with multi-select list scrolls to the top after selecting an item making it difficult to select multiple items in the list box control.
* (SelectMultiComponent autoTopIndex, autoTopValue) Added methods #topIndex and #topValue to allow obtaining the index or value of the first visible item, at the top of the list box. The new options autoTopIndex and autoTopValue will be consumed on first render, affecting the listbox scroll position appropriately.
* (SelectBaseComponent) NPE occurring, after a component had been detached from the dashboard. Events would still fire and cause the error.
* Added placeholder method to BaseComponent.
Merge branch '5.0' of https://github.com/webdetails/cdf into 5.0