Implement CbmStsDigi version without ROOT dependencies

refs #2258 refs #2259 Remove ROOT data types from CbmStsDigi. Also remove the dependency to RtypesCore.h. The change of the data types has no influence on the streamer. It is still possible to read previous versions from file even without increasing the version number.

Implement new directory structure below the algo directory.

Add new CbmOnlineData library The new library currently only contains a ROOT free version of CbmStsDigi. The code is still in core/data/sts. The class CbmStsDigi is currently compiled twice. Once with ROOT dictionary an streamer in libCbmData and once without any ROOT dependency in libCbmOnlineData. refs #2258