The big dadaflow merge
Dadaflow is now separated from the rest of the cmake build in its own submodule. This is not enabled by BUILD_SUBMODULES but by a new option BUILD_DADAFLOW (defaulted to OFF).
A couple of concerns here:
- the inclusion of the mathdx dependency is not well handled at the moment.
- this changes the C++ language standard in cmake
- Additional warning have been enabled. The merge request includes some fixes to non-dadaflow parts of psrdada_cpp