Added kdims declaration to HoloMap example on homepage
Added kdims declaration to HoloMap example on homepage

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