Pin aws-sdk to v1
Pin aws-sdk to v1

to address failures in https://travis-ci.org/travis-ci/travis-core/builds/50080196

travis-ci/travis-core,final-ci/travis-core,kidaa/travis-core,final-ci/travis-core,Tiger66639/travis-core,travis-ci/travis-core,Tiger66639/travis-core,GistIcon/travis-core,Tiger66639/travis-core,developerfm/travis-core,developerfm/travis-core,kidaa/travis-core,GistIcon/travis-core,developerfm/travis-core,final-ci/travis-core,GistIcon/travis-core,kidaa/travis-core,travis-ci/travis-core