More standard ways of linking other allocators - Correctly apply tc-malloc recommended flags.
Changes are:
- Correctly cancel the built-ins to malloc and friends that GCC and friends use when compiling with an alternative allocator library.
- Add the option to link in TBBmalloc following the same pattern as tcmalloc and jemalloc.
- Make sure we do not have more than one alternative allocator library linked in.
- Update the README.
- Also make use of the alternative allocators in the unit tests.
- Print the allocator choice into the snapshot meta-data.
Edited by Matthieu Schaller