docs/build: added info about juju.
docs/build: added info about juju.

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