Allow custom mousemove conditions for Select interaction

When configuring a Select interaction with a custom condition that includes mousemove, panning the map will not work any more. This is because the return value of handleMapBrowserEvent is determined by checking for a default condition function. By checking for the underlying event type instead, we gain flexibility with custom condition functions.

This change makes Select interaction configurations like the following work:
```js
new ol.interaction.Select({
  condition: function(evt) {
    return evt.originalEvent.type == 'mousemove' ||
        evt.type == 'singleclick';
  }
});
```
This configuration is useful for hover selection with a click fallback on mobile devices that do not have hover.