fix occ upgrade to not bail when occ returns 'ownCloud is already latest version' exit code 3, see #496
fix occ upgrade to not bail when occ returns 'ownCloud is already latest version' exit code 3, see #496

ianberinger/mailinabox,choltha/mailinabox,nstanke/mailinabox,d5ve/mailinabox,ianberinger/mailinabox,pierreozoux/mailinabox,ianberinger/mailinabox,pierreozoux/mailinabox,b-deng/mailinabox,Neopallium/mailinabox,b-deng/mailinabox,pierreozoux/mailinabox,b-deng/mailinabox,d5ve/mailinabox,nstanke/mailinabox,m4rcs/mailinabox,d5ve/mailinabox,ianberinger/mailinabox,Neopallium/mailinabox,m4rcs/mailinabox,d5ve/mailinabox,jjz/mailinabox,jprice/mailinabox,jjz/mailinabox,mail-in-a-box/mailinabox,pierreozoux/mailinabox,Neopallium/mailinabox,nstanke/mailinabox,b-deng/mailinabox,m4rcs/mailinabox,choltha/mailinabox,Neopallium/mailinabox,d5ve/mailinabox,choltha/mailinabox,choltha/mailinabox,jjz/mailinabox,ianberinger/mailinabox,jjz/mailinabox,nstanke/mailinabox,jprice/mailinabox,mail-in-a-box/mailinabox,pierreozoux/mailinabox,jprice/mailinabox,m4rcs/mailinabox,m4rcs/mailinabox,jprice/mailinabox,b-deng/mailinabox,mail-in-a-box/mailinabox,jjz/mailinabox,nstanke/mailinabox,choltha/mailinabox,Neopallium/mailinabox,mail-in-a-box/mailinabox,jprice/mailinabox