The first version of new path test program. The old became old_path_test.

KeySet and ValueSet are inserted into the map structures.
They makes possible the iterating on the keys or values only.

... and add the missing header files.

- hugo/skeletons/path.h added.
- Obsolete XYZ_map_factory.h's removed.

Improve docs.

Spell checking (Ereasable ->Erasable), affected also the code.

Improved docs.

Shorter template parameter names to be more readable in Doxygen.

There was a little troublie with the true return statement

The MapFactories have been removed from the code because
if we use macros then they increases only the complexity.

The pair iterators of the maps are separeted from the maps.

Some macros and comments has been changed.