* Add a test case for updating jumplists across windows
* Apply transactions to all views on history changes
This ensures that jumplist selections follow changes in documents, even
when there are multiple views (for example a split where both windows
edit the same document).
* Leave TODOs for cleaning up View::apply
* Use Iterator::reduce to compose history transactions
Co-authored-by: Blaž Hrastnik <blaz@mxxn.io>
Co-authored-by: Blaž Hrastnik <blaz@mxxn.io>