BUG: Fix format string for Python-2.6
BUG: Fix format string for Python-2.6

rgommers/pywt,grlee77/pywt,aaren/pywt,eriol/pywt,grlee77/pywt,PyWavelets/pywt,ThomasA/pywt,michelp/pywt,PyWavelets/pywt,rgommers/pywt,kwohlfahrt/pywt,aaren/pywt,ThomasA/pywt,eriol/pywt,michelp/pywt,kwohlfahrt/pywt,aaren/pywt,rgommers/pywt,michelp/pywt,ThomasA/pywt,rgommers/pywt,kwohlfahrt/pywt,eriol/pywt