fix auth-type, now allowed to be blank, plain, or crammd5
fix auth-type, now allowed to be blank, plain, or crammd5

wikimedia/operations-debs-burrow,spredfast/Burrow,samklr/Burrow,wilmer-daza/Burrow,Connexity/Burrow,evertrue/Burrow,ContentSquare/Burrow,linkedin/Burrow,wikimedia/operations-debs-golang-burrow,WanliTian/Burrow,ehorne/Burrow,jhollandus/Burrow,IndraVikas/Burrow,socrata/Burrow,wikimedia/operations-debs-burrow,saleswise/Burrow,matsu-chara/Burrow