22.0-refactor-IOVDbSvc
Continue refactoring of IOVDbSvc. Push increasing parse functionality from the IOVDbFolder class to the IOVDbParser, take out the IOV caches in IOVDbFolder into a new separate IOVStore class. Take (some) tag resolving functionality from IOVDbFolder into standalone functions, TagFunctions.h/.cxx. Produce new unit tests and extend the previous ones fro the new functionality. Move repetitive code for CoraCool and Cool objects into a templated section so it's not repeated for the different cases.
Edited by Shaun Roe