In some client-server test cases, messages are supposed to be injected into
the instance 2(client), but they are actually injected into instance 1(server),
which may lead to false negative results. This patch fixed it by replacing
'injectmsg' with 'injectmsg2', and dealt with some minor issues.
Also now permit interactivly running tests without explicitly setting
$srcdir. This now works if we are inside ./tests and fails, as before,
when we are in a different directory.
Detected by shellcheck via CodeFactor.io
Add SNI hostname if and only if host is not a bare IP address
Rename sndrcv_tls_anon -> sndrcv_tls_anon_hostname, and include a hostname in this test
Add bare IPv4 and IPv6 TLS tests
Change port in some tests to make wireshark traces easier to interpret during a full test run
