Write cell filter parameters to a h5 file

write_cell_filter_parameters(h5_file, cell_filter_parameters)

Arguments

h5_file	Path to `h5` file
cell_filter_parameters	A `list` of filter parameters (see details)

The cell filter parameters list is named by the UI element label and contains:

var the variable from metadata (which should be a factor) that is to be filtered
selected the levels that are selected by default