Search highlighting across multiple buffers

[ChoppinBlockParty]

Provide a pilot version as PoC. No cross-buffer highlighting for substitution in this version. On the way improve overall performance of highlighting by removing run-at-time and introducing window-end with update equal t.

Search pattern in Vim is highlighted in every visible buffer, this does not sound like a big deal, however it is very useful in many small situations. This feature is also addressed in issue #805.

Please, try it out, feedback is highly appreciated. I have tested it quickly on few buffers with some large content as well (like ~20k) worked well, I think the previous version with timer was lagging much more. After some feedback and a few days of real life testing, I will polish this one to be ready for merge.

[ChoppinBlockParty]

Hello Guys, I have been using this one for more than a year it is working well. Can we consider merging it?

[TheBB]

Sorry. :-)

I'll have a look this week hopefully.