add IRTAlgorithm

close #73 #16 (closed)

• add https://eicweb.phy.anl.gov/EIC/irt package (see irt!1 (merged))
• pipelines will fail until IRT is available in the container, and eicd!65 (closed) is merged
• add Jug::PID::IRTAlgorithm, to connect Juggler to the IRT code
• add IRT env var to .gitlab-ci.yml and find_package to CMakeLists.txt