Allow retrieval of the default filter on a dataView
Allow retrieval of the default filter on a dataView

 * This allows using the original default filter in a custom filter
 * Means I dont have to rewrite the full default filter to add a new
   addition
 * Should allow multiple passes of replaceing a filter with one that
   extends the previous one.

6pac/SlickGrid,cheminfo/SlickGrid,yamass/SlickGrid,6pac/SlickGrid,yamass/SlickGrid,cheminfo/SlickGrid,cheminfo/SlickGrid