add TTree support for DQ algorithms
Addresses ATLASDQ-665 (adds TTree support to AthenaMonitoringKernel). WIP until !29214 (merged) is merged as there are a couple of minor tweaks to adjust to the updated API.
User interface specifies TTree branches using the new "treeDef" argument of the new defineTree. All the standard TTree primitive types (except for C = C null-terminated string) are supported, as is "string" and a number of vector types (float, double, char, int, long, and the unsigned versions of the integer types).
Cherry-picks a commit from !29191 (merged) (for proper MT operation).
Edited by Peter Onyisi