* test4issue373:
  Extend test_issue373 to test also with QoS 1 and 2
  Add helper script for test_issue373 to cyclically disconnect the VM running the broker
  Add log output for failed message queueing in test due to disconnect
  Do not reduce the tcp send buffer size for production code

# Conflicts:
#	test/test_issue373.c
Signed-off-by: Juergen Kosel <juergen.kosel@softing.com>