Fix panic when resizing
Fix panic when resizing

The selection might have a beginning or end that is outside the bounds
after a resize and cause a panic on subsequent draws. Easy solution is
to just clear the selection on resize.

jwilm/alacritty,jwilm/alacritty,jwilm/alacritty,alacritty/alacritty,jwilm/alacritty,alacritty/alacritty