Pipe validation to check initialisation code in metadata classes

[jgalan]

All metadata classes must define at its initialisation stage the corresponding class name, and the LIBRARY_VERSION. Which is usually as follows:

void TRestMetadataClass::Initialize() {
    SetSectionName(this->ClassName());
    SetLibraryVersion(LIBRARY_VERSION);
}

We need a script running at the pipeline before the build stage to assure this is as that. This will only be tested at metadata classes under source/libraries. It could be inspired by pipeline/validateProcesses.py