Part of #1148

As per request by Kostja, commit an RFC document with a brief history of
the vinyl metadata log infrastructure, issues it was intended to solve,
problems we are facing now, and possible ways to solve them.

Part of #4182

Part of #3271

Add description of possible redesigning of vector clocks.

This is a draft paper covering following topics:
1. Draft protocol for discovering and maintaining network topology
in case of large arbitrary network.
2. List of required changes to support this feature.
3. Open questions and alternatives.

Changes in V2:
Based or Vlad's review
1. Rewrite couple sections to make it more clear.
2. Clarify with more details and add examples.
3. Fixed error.

RFC for #3294

Part of #3328

Introducing a formal, trackable process for server enhancement.

Before working on a complex feature, please write an RFC document,
describing what and how you see changed, and get it approved.

All historical RFCs are kept in doc/rfc.

* update tarantool man page
* cross-reference tarantool and tarantoolctl pages

Moved to tarantool/doc repository.

* doc: moved to http://github.com/tarantool/doc

Fixed Lua code block formatting in box_index.rst

* wallarm button alignment
* better action calls
* remove obsolete benchmarks & example