Reverted travis configuration to pip
Reverted travis configuration to pip

mjabri/holoviews,ioam/holoviews,basnijholt/holoviews,vascotenner/holoviews,mjabri/holoviews,vascotenner/holoviews,ioam/holoviews,ioam/holoviews,mjabri/holoviews,vascotenner/holoviews,basnijholt/holoviews,basnijholt/holoviews