Initially, I wanted to do the simulation inside neoctl but it has no knowledge
of the topology (the master don't send devpath values of storage nodes).
Therefore, the work is delegated to the master node, which implies a change
of the protocol.

This stops abusing ProtocolError, which disconnects the admin node needlessly.

The many 'if ... raise RuntimeError' in neo/neoctl/neoctl.py
could be turned into assertions.

neoctl gets a new command to change the number of replicas.

The number of replicas becomes a new partition table attribute and
like the PT id, it is stored in the config table. On the other side,
the configuration value for the number of partitions is dropped,
since it can be computed from the partition table, which is
always stored in full.

The -p/-r master options now only apply at database creation.

Some implementation notes:

- The protocol is slightly optimized in that the master now sends
  automatically the whole partition tables to the admin & client
  nodes upon connection, like for storage nodes.
  This makes the protocol more consistent, and the master is the
  only remaining node requesting partition tables, during recovery.

- Some parts become tricky because app.pt can be None in more cases.
  For example, the extra condition in NodeManager.update
  (before app.pt.dropNode) was added for this is the reason.
  Or the 'loadPartitionTable' method (storage) that is not inlined
  because of unit tests.
  Overall, this commit simplifies more than it complicates.

- In the master handlers, we stop hijacking the 'connectionCompleted'
  method for tasks to be performed (often send the full partition
  table) on handler switches.

- The admin's 'bootstrapped' flag could have been removed earlier:
  race conditions can't happen since the AskNodeInformation packet
  was removed (commit d048a52d).

Besides the use of another module for option parsing, the main change is that
there's no more Config class that mixes configuration for different components.
Application classes now takes a simple 'dict' with parsed values.

The changes in 'neoctl' are somewhat ugly, because command-line options are not
defined on the command-line class, but this component is likely to disappear
in the future.

It remains possible to pass options via a configuration file. The code is a bit
complex but isolated in neo.lib.config

For SSL, the code may be simpler if we change for a single --ssl option that
takes 3 paths. Not done to not break compatibility. Hence, the hack with
an extra OptionList class in neo.lib.app

A new functional test tests the 'neomigrate' script, instead of just the
internal API to migrate data.

- format IPv6 inside [] when followed by :<port>
- unify rendering of node lists
- neoctl: do not crash on empty DB (no PT id)

Currently, the command "neoctl [arguments] print ids" has the following output:

    last_oid = 0x...
    last_tid = 0x...
    last_ptid = ...

or

    backup_tid = 0x...
    last_tid = 0x...
    last_ptid = ...

depending on whether the cluster is in normal or backup mode.

This is extremely unreadable since the admin is often interested in the time that corresponds to each tid. Now the output is:

    last_oid = 0x...
    last_tid = 0x... (yyyy-mm-dd hh:mm:ss.ssssss)
    last_ptid = ...

or

    backup_tid = 0x... (yyyy-mm-dd hh:mm:ss.ssssss)
    last_tid = 0x... (yyyy-mm-dd hh:mm:ss.ssssss)
    last_ptid = ...

/reviewed-on !2

With the previous commit, the request to truncate the DB was not stored
persistently, which means that this operation was still vulnerable to the case
where the master is restarted after some nodes, but not all, have already
truncated. The master didn't have the information to fix this and the result
was a DB partially truncated.

-> On a Truncate packet, a storage node only stores the tid somewhere, to send
   it back to the master, which stays in RECOVERING state as long as any node
   has a different value than that of the node with the latest partition table.

We also want to make sure that there is no unfinished data, because a user may
truncate at a tid higher than a locked one.

-> Truncation is now effective at the end on the VERIFYING phase, just before
   returning the last ids to the master.

At last all nodes should be truncated, to avoid that an offline node comes back
with a different history. Currently, this would not be an issue since
replication is always restart from the beginning, but later we'd like they
remember where they stopped to replicate.

-> If a truncation is requested, the master waits for all nodes to be pending,
   even if it was previously started (the user can still force the cluster to
   start with neoctl). And any lost node during verification also causes the
   master to go back to recovery.

Obviously, the protocol has been changed to split the LastIDs packet and
introduce a new Recovery, since it does not make sense anymore to ask last ids
during recovery.

Application will hold SSL parameters.

For example, a backup storage node that was rejected because the upstream
cluster was not ready could reconnect in loop without delay, using 100% CPU
and flooding logs.

A new 'setReconnectionNoDelay' method on Connection can be used for cases where
it's legitimate to quickly reconnect.

With this new delayed reconnection, it's possible to remove the remaining
time.sleep().