include/cppunit/config/Portability.h: If the compiler does not support
namespace (CPPUNIT_HAVE_NAMESPACES=0), define CPPUNIT_NO_STD_NAMESPACE
and CPPUNIT_NO_NAMESPACE. If CPPUNIT_NO_STD_NAMESPACE is defined, then
CppUnit assumes that STL are in the global namespace. If
CPPUNIT_NO_NAMESPACE is defined, then CppUnit classes are placed in the
global namespace instead of the CppUnit namespace.

* include/cppunit/config/config-bcb5.h:
* include/cppunit/config/config-msvc6.h: added definition of macro
CPPUNIT_HAVE_NAMESPACES.

* include/cppunit/tools/StringTools.h: use CPPUNIT_WRAP_COLUMN as default
parameter value for wrap().

* include/cppunit/*/*.h:
* src/cppunit/*.cpp: changed all CppUnit namespace declaration to use
macros CPPUNIT_NS_BEGIN and CPPUNIT_NS_END. Also, changed reference
to CppUnit namespace (essentially in macros) using CPPUNIT_NS macro.