The universal application works well, but is quite difficult to extend
with more functionality. Therefore a new and more modular application is
needed. The new dctool application will support multiple sub-commands,
to carry out specific actions. Extending the application will be as easy
as adding new commands.
The public api is changed to require a context object for all
operations. Because other library objects store the context pointer
internally, only the constructor functions need an explicit context
object as a parameter.
The public header files are moved to a new subdirectory, to separate
the definition of the public interface from the actual implementation.
Using an identical directory layout as the final installation has the
advantage that the example code can be build outside the project tree
without any modifications to the #include statements.
