added servicestatus test and assertion; pretty print of XML file
added servicestatus test and assertion; pretty print of XML file

energyos/OpenESPI-GreenButtonCMDTest,dfcoffin/OpenESPI-GreenButtonCMDTest,MartyBurns/OpenESPI-GreenButtonCMDTest,RonPasquarelli/OpenESPI-GreenButtonCMDTest,dfcoffin/OpenESPI-GreenButtonCMDTest,MartyBurns/OpenESPI-GreenButtonCMDTest,RonPasquarelli/OpenESPI-GreenButtonCMDTest,energyos/OpenESPI-GreenButtonCMDTest