HH-44624 remove deprecated service_mock methods
HH-44603 add new tests
HH-44603 drop python 2.6
HH-44603 add coverage
HH-44603 add tests for default urls
Merge remote-tracking branch 'origin/HH-44624' into EXP-11719
Merge remote-tracking branch 'origin/HH-44603' into EXP-11719
release 2.20.10 [an.sumin@hh.ru]
tornado-3 fix send_error
update to new tornado_util and other new tornado fixes