Added a basic threshold ViewOperation to operation
Added a basic threshold ViewOperation to operation

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