update Pythia8_i and Pythia8B_i to current status
it is to update interfaces for Pythia8_i and Pythia8B_i to the standard used in rel. 21.6 in particular allowing to run these interfaces with Pythia8.3xx series. New user Hooks were added and code modifications were introduced which make the changes needed for the new version, as well as fixing some problems found in the interface.