Adding code to SearchConceptHelper to clear existing search filters from
SearchTypeModel before loading saved search criteria; adding code to
EnhancedSavedSearch to trigger invocation of searchType change button
cell factory and change handlers after load of saved search; adding code
to SearchTypeSelector.changeSearchType() to gracefully handle (ignore)
selection of null SearchType in order to allow reselection of current
type, which will trigger GUI updates; changing TextSearchTypeView code
to remove specified filter from removeFilterButton handler into method
that can also be called from elsewhere, including on selection of
searchType