try fixing travis-ci/travis-ci#5909
try fixing travis-ci/travis-ci#5909
mschreiber/packagedrone,eclipse/packagedrone,ibh-systems/packagedrone,mschreiber/packagedrone,eclipse/packagedrone,ibh-systems/packagedrone,eclipse/packagedrone,mschreiber/packagedrone,ibh-systems/packagedrone,eclipse/packagedrone,ibh-systems/packagedrone,mschreiber/packagedrone