Trusted CA dir in security configuration is optional, but participant
creation currently fails if no or empty dir is provided. This commit
fixes this issue and adds some tests for various trusted_ca_dir values.
Signed-off-by: Dennis Potman <dennis.potman@adlinktech.com>
updated plugin loading tests to use these instead of specific wrappers per test. Added
test for securing communication ad handshake fail (using different identity CAs)
Signed-off-by: Dennis Potman <dennis.potman@adlinktech.com>