docs: added link to backup section in the index page
docs: added link to backup section in the index page

Closes #234.

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