Merge branch 'stable-2.12' into stable-2.13

Merge branch 'stable-2.12' into stable-2.13

* stable-2.12
  Handle SSL setup when downgrading
  Write SSH ports to ssconf files
  Noded: Consider certificate chain in callback
  Cluster-keys-replacement: update documentation
  Backend: Use timestamp as serial no for server cert
  UPGRADE: add note about 2.12.5
  NEWS: Mention issue 1094
  man: mention changes in renew-crypto
  Verify: warn about self-signed client certs
  Bootstrap: validate SSL setup before starting noded
  Clean up configuration of curl request
  Renew-crypto: remove superflous copying of node certs
  Renew-crypto: propagate verbose and debug option
  Noded: log the certificate and digest on noded startup
  QA: reload rapi cert after renew crypto
  Prepare-node-join: use common functions
  Renew-crypto: remove dead code
  Init: add master client certificate to configuration
  Renew-crypto: rebuild digest map of all nodes
  Noded: make "bootstrap" a constant
  node-daemon-setup: generate client certificate
  tools: Move (Re)GenerateClientCert to common
  Renew cluster and client certificates together
  Init: create the master's client cert in bootstrap
  Renew client certs using ssl_update tool
  Run functions while (some) daemons are stopped
  Back up old client.pem files
  Introduce ssl_update tool
  x509 function for creating signed certs
  Add tools/common.py from 2.13
  Consider ECDSA in SSH setup
  Update documentation of watcher and RAPI daemon
  Watcher: add option for setting RAPI IP
  When connecting to Metad fails, log the full stack trace
  Set up the Metad client with allow_non_master
  Set up the configuration client properly on non-masters
  Add the 'allow_non_master' option to the WConfd RPC client
  Add the option to disable master checks to the RPC client
  Add 'allow_non_master' to the Luxi test transport class too
  Add 'allow_non_master' to FdTransport for compatibility
  Properly document all constructor arguments of Transport
  Allow the Transport class to be used for non-master nodes
  Don't define the set of all daemons twice

Conflicts:
  Makefile.am
  NEWS
  UPGRADE
  lib/client/gnt_cluster.py
  lib/cmdlib/cluster.py
  lib/tools/common.py
  lib/tools/prepare_node_join.py
  lib/watcher/__init__.py
  man/ganeti-watcher.rst
  src/Ganeti/OpCodes.hs
  test/hs/Test/Ganeti/OpCodes.hs
  test/py/cmdlib/cluster_unittest.py
  test/py/ganeti.tools.prepare_node_join_unittest.py
  tools/cfgupgrade

Resolutions:
  Makefile.am:
    add ssl_update and ssh_update
  NEWS:
    add new sections from 2.12 and 2.13
  UPGRADE:
    add notes for both 2.12 and 2.13
  lib/client/gnt_cluster.py:
    add all new options to RenewCluster, remove version-specific
    downgrade code
  lib/tools/common.py:
    split the two mismatching versions of _VerifyCertificate
    and VerifyCertificate up into [_]VerifyCertifcate{Soft,Strong}
    and update usages accordingly
  lib/tools/prepare_node_join.py
    update usage of correct VerifyCertificate function
  lib/watcher/__init__.py
    add both new options, --rapi-ip and --no-verify-disks
  man/ganeti-watcher.rst
    update docs for both new options (see above)
  src/Ganeti/OpCodes.hs
    add all new options to OpRenewCrypto
  test/hs/Test/Ganeti/OpCodes.hs
    add enough 'arbitrary' for all new options of OpRenewCrypto
  test/py/cmdlib/cluster_unittest.py
    use changes from 2.12
  test/py/ganeti.tools.prepare_node_join_unittest.py
    remove tests that were moved to common_unittest.py
  tools/cfgupgrade
    use only downgrade code of 2.13

Signed-off-by: Helga Velroyen <helgav@google.com>
Reviewed-by: Petr Pudlak <pudlak@google.com>