Add OtherLine to hi groups apply order tree
Pull print_width calculation out of draw_cell()

It's more convenient for one of its uses (see next commit).
Fix other line highlight when 'lsview' is on
Fix OtherLine highlight for selected items

Thanks to Svyatoslav Mishyn, a.k.a. juef.
Merge branch 'fixes-for-other-line-hi-group'

* Fix OtherLine highlight for selected items.
* Fix OtherLine highlight when 'lsview' is on.
* Document OtherLine in hi groups hierarchy.