Raft Consensus - System Test

A new consensus option, etcd/raft, is being developed for the next release with FAB-6135. This is an associated epic to identify the tools and testcases necessary for system testing.

This is where add all system verification tests (SVT) involving the etcd/raft-based ordering service.

A few guidelines:

1. We'll be adding a test task per test.
2. For each test, we describe the test's setup, inputs, and expected outputs in detail.
3. We'll avoid acronyms as much as possible, and go with descriptions in plain english.
4. We'll keep logs of both successful and unsuccessful runs around.

Anything that applies to all system verification tests should be recorded as a comment under this epic.