Among the changes:
- It removes the ``and, or, not`` keywords
- It updates the Documentation
- It moves the internal structures in the ``details::`` namespace
It seems that on recent version on the SDK, Microsoft renamed the
field LoadConfiguration::reserved1 into DependentLoadFlags.
This commit create an alias on this field
Resolve#621
* JSON visitor are located in the format namespace
* Visitor are *real* visitor
* Visitable class has been renamed to Object
* Due to a bug in Visual Studio 2015, we move to VS2017
Romain Thomas