Trim down Travis, cache pip
Trim down Travis, cache pip

nteract/composition,captainsafia/nteract,0u812/nteract,nteract/composition,rgbkrk/nteract,jdetle/nteract,jdfreder/nteract,rgbkrk/nteract,0u812/nteract,nteract/composition,rgbkrk/nteract,captainsafia/nteract,jdfreder/nteract,rgbkrk/nteract,rgbkrk/nteract,nteract/nteract,jdfreder/nteract,jdetle/nteract,0u812/nteract,nteract/nteract,jdetle/nteract,nteract/nteract,nteract/nteract,temogen/nteract,jdfreder/nteract,captainsafia/nteract,0u812/nteract,temogen/nteract,jdetle/nteract,captainsafia/nteract,temogen/nteract,nteract/nteract