cmd/tsuru: check for errors when guessing app name in app-remove
cmd/tsuru: check for errors when guessing app name in app-remove

Fix #181.

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