Add option run test with a user defined command in scons
Using pip to install unittest2py3k
Install install2 with easy_install
Use relpath first, and then abspath.

This accounts for error reported w.r.t. the fix for ticket #56.
Resolving ticket #88

Use a Python path relative to the location of this file if
the Python cxxtest package has not been installed.
Adding rc status for test output failures.