readme: fixed build status @ travis-ci.
readme: fixed build status @ travis-ci.

Signed-off-by: Francisco Souza <8d45e0355693b8ec0dbbcdd5571f92a74ecfcbc2@corp.globo.com>

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