queue: use safe.Counter instead of custom counter
queue: use safe.Counter instead of custom counter

ggarnier/tsuru,ArxdSilva/tsuru,RichardKnop/tsuru,Endika/tsuru,firebitsbr/tsuru,4eek/tsuru,RichardKnop/tsuru,gwmoura/tsuru,tsuru/tsuru,tuxmonteiro/tsuru,tuxmonteiro/tsuru,Endika/tsuru,gwmoura/tsuru,hcxiong/tsuru,kgrvamsi/tsuru,cezarsa/tsuru,gwmoura/tsuru,mderaldo/tsuru,4eek/tsuru,firebitsbr/tsuru,guilhermebr/tsuru,mderaldo/tsuru,ggarnier/tsuru,cezarsa/tsuru,guilhermebr/tsuru,tsuru/tsuru,cezarsa/tsuru,mderaldo/tsuru,kgrvamsi/tsuru,cgvarela/tsuru,ggarnier/tsuru,gciotta/tsuru,ArxdSilva/tsuru,guilhermebr/tsuru,gciotta/tsuru,tsuru/tsuru,jblancett/tsuru,hugoantunes/tsuru,hcxiong/tsuru,tuxmonteiro/tsuru,ggarnier/tsuru,cgvarela/tsuru,firebitsbr/tsuru,RichardKnop/tsuru,ArxdSilva/tsuru,ArxdSilva/tsuru,hcxiong/tsuru,Endika/tsuru,cezarsa/tsuru,tsuru/tsuru,jblancett/tsuru,gciotta/tsuru,jblancett/tsuru,cgvarela/tsuru,kgrvamsi/tsuru,guilhermebr/tsuru,4eek/tsuru,hugoantunes/tsuru