added :setSelectionColor()

added :setSelectionColor(backgroundCol, foregroundCol)

Basalt/objects/Textfield.lua

@@ -686,6 +686,12 @@ return function(name)
             end
         end,
         
+        setSelectionColor = function(self, bg, fg)
+            selectionBG = bg or selectionBG
+            selectionFG = fg or selectionFG
+            return self
+        end,
+
         draw = function(self)
             if (base.draw(self)) then
                 if (self.parent ~= nil) then