This regtest tests the issue #446 by starting 2 programs and checking if
they exist in the "show proc" of the master CLI.
Should be backported as far as 2.0.
VTest can now enable mworker and mcli with separate flags so lets
update vtc files that need it. This also allows to revert the change
made with 1545a59c ("REGTESTS: make seamless-reload depend on 1.9
and above").
This test launches a HAProxy process in master worker with 'nbproc 4'.
It sends a "show info" to the process 3 and verify that the right
process replied.
This regtest depends on the support of the master CLI for VTest.