Adding a --force-colour option to force colour output on POSIX systems,
provided a debugger is not attached.
This allows for Catch to output colours even if STDOUT is not a tty,
which can be the case when the test executable is being spawned by a
parent process (e.g. CMake's ctest).
Added !throws special tag which denotes a test case to be skipped when run with -e
(the idea being that the test case is expected to throw an exception which is not caught within a XXX_THROWS assertion).
- started integrating with reporters (now (optionally) supported in console reporter).
- introduced Node<> template to help with cumulative reporting and used it instead of ThreadedSectionInfo.
