Merge branch 'socket_connect_timeout' into 'master'

doc/man/knot.conf.5in

doc/reference.rst

src/knot/conf/scheme.c

src/knot/ctl/knotc_main.c

src/knot/modules/dnsproxy.c

src/knot/server/tcp-handler.c

src/knot/zone/events/handlers.c

src/libknot/internal/net.c

src/libknot/internal/net.h

src/libknot/processing/requestor.c

tests-extra/tests/events/soa/data/example.zone

tests-extra/tests/events/soa/data/example.zone.1

tests-extra/tests/events/soa/data/example.zone.2

tests-extra/tests/events/soa/test.py

tests-extra/tests/zone/expire/test.py

tests-extra/tests/zone/timers/test.py

tests-extra/tools/dnstest/server.py

tests/net_shortwrite.c

tests/requestor.c