Make the searching query to be the non-selected text, not the full text

For example, if we have two notes "Car" and "Care", when we type "Ca", then it automatically fills "Care" and drops "Car". (Assume "Care" comes ahead of "Car"). However, we still want to search with "Ca".

lib/notational-velocity-view.coffee

@@ -115,6 +115,12 @@ class NotationalVelocityView extends SelectListView
   hide: ->
     @panel?.hide()
 
+  getFilterQuery: ->
+    editor = @filterEditorView.model
+    fullText = editor.getText()
+    selectedText = editor.getSelectedText()
+    return fullText.substring(0, fullText.length - selectedText.length)
+
   populateList: ->
     filterQuery = @getFilterQuery()
     filteredItems = null