Look for places to use new requires_redraw metadata

**Problem Description**
In PR #585 we added the `requires_redraw` metadata to specify that if a particular trait changes, `invalidate_and_redraw` should be called. We should sweep the code bases for all possible cases where we could use this, eg for things like:
```
def _sometrait_change(self):
self.invalidate_draw()
self.request_redraw()
```