Very early concept of v9

[mishamyte]

Hey guys!

Now I'm almost at the beginning of thinking of v9 version of this sink.

I haven't made any concrete decisions, but have some ideas:

• Rethink main public "points of extensibility" (some of them doesn't satisfy us anymore and interfere us to fix some bugs)
• Rewrite sink to F# (I'm thinking about it some time, didn't made it for v8, but it is still on. It will help me to write more readable code, use some F# excellent tools and drop off this single-method files-classes)
• Infrastructure part (this stuff with a portable timer came from fork and one lib, which were in base of this sink. But later was deleted because of it's breaking changes. Honestly, I believe that there are more efficient ways to work with concurrent data that using timer, concurrent queue and a lot of locks)
• ???

So this is a base for now. I will be glad to hear from you what functionality are you missing or maybe some use cases of this sink, that can't be done with v8.

P.S. Yep, I'm keeping returning of durable mode in my mind, but there are some tricky parts, so it won't be a part of v9 (I think so)

Thanks!