Migrate core/data to C/C++ std integer types
This migrates almost everything in core/data to C/C++ standard integer types and the standard math library.
It is meant as a first step towards making the ROOT dependency of the core/data classes optional. As it mostly just changes the source code from one set of #include's and typedef's to another, I do not expect compatibility issues with the rest of the project.
The removal of the dependency on TObject is not yet included in this change.