- loading of all objects (including H3 objects) will be directed by mod handlers
- common base for all handlers accessible from mod system (IHanderBase)
- json format changes: use struct with string ID's instead of vector
- fixed some gcc/clang errors and warnings
- fixed several cases of memory leaks and invalid memory access (mostly related to usage of bonus system and/or identifiers resolution)
Note that right now loading is much slower than before due to excessive json validation (or not fast enough validator)