Add principal-field documentation to Oauth
Add principal-field documentation to Oauth

dain/presto,smartnews/presto,Praveen2112/presto,dain/presto,losipiuk/presto,losipiuk/presto,losipiuk/presto,11xor6/presto,smartnews/presto,Praveen2112/presto,ebyhr/presto,dain/presto,dain/presto,Praveen2112/presto,Praveen2112/presto,smartnews/presto,losipiuk/presto,Praveen2112/presto,losipiuk/presto,smartnews/presto,11xor6/presto,dain/presto,11xor6/presto,ebyhr/presto,ebyhr/presto,11xor6/presto,ebyhr/presto,ebyhr/presto,smartnews/presto,11xor6/presto