NEO 1.12

* tag 'v1.12': (28 commits)
  Release version 1.12
  master: reject drop/tweak ctl commands that could lead to unwanted status
  qa: extend test reproducing the migration of a big ZODB to NEO
  neoctl: better display of full partition tables
  Bump protocol version
  tweak: add option to simulate
  tweak: do not crash when trying to remove all nodes
  tweak: do not touch cells of nodes that are intended to be dropped
  Better error reporting from the master to neoctl for denied requests
  Make 'neoctl print pt' report the number of replicas
  Make the number of replicas modifiable when the cluster is running
  New --new-nid storage option for fast cloning
  qa: fix 2 tests with ZODB5
  qa: new tools/stress options to evaluate MySQL engines
  qa: provide a way to let tests start 1 mysqld per storage node
  mysql: make 'user' actually optional in the DB connection string
  mysql: specify column families for RocksDB
  qa: add testIncremental (testImporter) test
  importer: fix hidden "maximum recursion depth exceeded" at startup
  importer: fix closure of ZODB, and also do it when the import is finished
  sqlite: fix resumption of migration to NEO with Importer
  qa: fix a random failure in threaded tests
  importer: speed up startup when the import is already finished
  importer: fix replication (as source) once import is finished
  storage: fix DatabaseManager.getLastTID with max_tid
  qa: remove 2 useless unit tests
  storage: allow the master to change our node id
  Rename --uuid command-line options into --nid
  importer: fix possible data loss on writeback