Cleaning imports in class base/Parallel.
Cleaning imports in class base/ParameterMap.
Cleaning imports in class base/Version.
Mixing in SGString/SG*Vector/SG*Matrix/CSerializableFile in funny places:
In places that are using it and don't include it (or having a superclass that includes).
Needed for fixing imports/forward declarations in base/Parallel.
Cleaning imports in class base/Parameter.
Cleaning imports in template for class base/class_list.cpp