Add optional/default animation bool to provide non-animated index sel…

[mattlisiv]

Hi,

Fantastic library! I recently used this segment control in a small project. I had a use case where I wanted to refresh a UIView that contained the TwicketSegmentedControl and default it to the current selection. However, because the move(to index: Int) was always animated, it became obvious the view was being refreshed.

I thought it may be beneficial to have the ability to move the selectedSegmentIndex without animation. The new optional/defaulting animation parameter on the move function should not affect any existing calls or break any code from what it appears.

Cheers! Matt