Re-organize public header files

[saschazelzer]

In anticipation of new modules in the source code, the public header files should be re-organized.

• Core headers will be located under include/us
• Other module headers will be located under include/<module>

All header files will be stripped of the "us" prefix and the us namespace will not be optional / changeable any more.

Header files also must not depend on configured information.

[karthikreddy09]

@jeffdiclemente
I like this idea ... headers in specific folders avoids conflict with similar named headers in global scope.

Would it make sense to use include/CppMicroServices instead of include/us ? I think it helps with readability in client code.

#include "CppMicroServices/Bundle.hpp"
vs
#include "us/Bundle.hpp"

[saschazelzer]

You are right, it is definitely more expressive, but also a lot more to type. I would like to get opinions from more people about this.

[lygstate]

I like #include "us/Bundle.hpp"