Fix some spelling in README.md
Fix some spelling in README.md

google/openhtf,grybmadsci/openhtf,grybmadsci/openhtf,amyxchen/openhtf,google/openhtf,ShaperTools/openhtf,jettisonjoe/openhtf,amyxchen/openhtf,jettisonjoe/openhtf,grybmadsci/openhtf,ShaperTools/openhtf,jettisonjoe/openhtf,google/openhtf,ShaperTools/openhtf,fahhem/openhtf,grybmadsci/openhtf,jettisonjoe/openhtf,fahhem/openhtf,ShaperTools/openhtf,google/openhtf,ShaperTools/openhtf,fahhem/openhtf,fahhem/openhtf