Tag for tdaq-09-04-00 addressing : * ADAMATLAS-422 - add parameter to control amount of raw data read for downsampling from local repository * ADAMATLAS-423 - fix duplication of merged files, when IS server is started with backup * ADAMATLAS-424 - improve downsampling of rarely updated raw data * ADAMATLAS-425 - implement "health" REST method for P-BEAST server