This file defines the namespace DDFF for dueca data format and dusime.

It defines the following macros:

• DDFF_NS_ON. If defined, this DUECA version uses namespace
• DDFF_NS_START. Used in DUECA code to indicate the start of the namespace. Defined as "namespace dueca { namespace ddff {".
• DDFF_NS_END. Used in DUECA code to indicate the end of the namespace. Defined as "}}".
• DDFF_NS. The name of the DUECA namespace, "dueca:ddff"
• USING_DDFF_NS. Defined as "using namespace dueca::ddff;"