docs/managing/using-pools: improve pool docs
docs/managing/using-pools: improve pool docs

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