fixed config loader to add registration access token; added a couple of negative API tests
fixed config loader to add registration access token; added a couple of negative API tests

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