GTestSuites
The GTestSuites class now derives from GContainer and implements
the usual container class methods (at(), size(), isempty(),
set(), append(), insert(), remove(), reserve() and extend()).
The operator[] now returns pointers to GTestSuite. The name()
and timestamp() methods now return const references.
GTestSuite
The GTestSuite class now derives from GBase. This implies that
the clone() method needs to be implemented for derived classes.
The test_assert() method now takes a const reference for the
boolean argument. The name(), errors(), failures(), and
timestamp() methods return const references. The obsolete
add_test() method has been removed.
The unit tests have been updated to conform to the new interfaces.
