ensure python 2.6 compatibility by backporting bits borrowed from standard unittest module
ensure python 2.6 compatibility by backporting bits borrowed from standard unittest module

aeron15/ruffus,jigneshvasoya/ruffus,pombreda/ruffus,magosil86/ruffus,pombreda/ruffus,bunbun/ruffus,kmonsoor/ruffus,d4g33z/ruffus