MINIFICPP-1481 - Extract flow id from url without bucket id
MINIFICPP-1481 - Extract flow id from url without bucket id

Signed-off-by: Arpad Boda <aboda@apache.org>

This closes #996

dtrodrigues/nifi-minifi-cpp,dtrodrigues/nifi-minifi-cpp,dtrodrigues/nifi-minifi-cpp,dtrodrigues/nifi-minifi-cpp,dtrodrigues/nifi-minifi-cpp