Added TextNode.selectEnd / Renamed TextNode.selectAfter to .selectNext

[zurfyx]

selectAfter works well most of the times. But there's some cases when the next Node is immutable that you either want to move the cursor before or after, not to the immutable node.

For reference:

if (nextSibling === null || !(nextSibling instanceof TextNode) || nextSibling.isImmutable() || nextSibling.isSegmented()) {
  throw new Error('This needs to be fixed');
}

This diff doesn't implement a recursive solution to the immutable nodes to follow, but the introduction of selectEnd should fix the first, move the cursor just at the end of the node you're working with.

That said, this diff is very opinionated so I'm happy to drop it entirely.

[trueadm]

So you want it to select the end of the immutable/segmented node? I thought this would break, because these types of nodes are marked as "contenteditable=false", so they should never be part of the selectable editor space.

[zurfyx]

@trueadm - The end of a mutable node. Place the cursor just at the end of that node

[trueadm]

This seems to break a bunch of tests, mind looking into it?

[zurfyx]

@trueadm - Sorry, shouldn't have published a half-baked PR. Added a new test for selectEnd and fixed the broken ones