Merge pull request #504 from euroelessar/master

Fixed several errors
v2.26.3.14
package: depend on blackhole 0.2.0-1 and higher
package: depend on blackhole 0.2.0-2 and higher
Python: completely removed old interface elliptics.Session.get_routes and used new elliptics.Session.routes wherever needed.
tools: added '-n/--check_nodes' option to dnet_balancer for printing only nodes spread without route-list.
merge recovery: added user-friendly log when group has only one node with one backend.
monitor: now monitor listen the same net family as the node does.
Pytests: added monitor statistics to log.
Pytest: marked each test case by unique trace_id.
Monitor: moved config of disabled backend to 'backend->config'
recovery: now if dc couldn't read the newer version of the key - it skips it and use next one by timestamp and so on.
monitor: forced deflate of the transmitted json.
Merge pull request #505 from shaitan/master

Batch of changes
monitor: added forgotten file.
Merge pull request #506 from euroelessar/master

elliptics: Fixed handler::total at several places
Merge pull request #507 from shaitan/master

monitor: added forgotten file.
v2.26.3.15
monitor: removed commands history.
Merge pull request #510 from shaitan/master

monitor: removed commands history.