Manual category updates

[cornhundred]

Is your feature request related to a problem? Please describe.
We would like to be able to

• edit more than one manual category at a time
• select all visible rows/columns to be assigned to a manual category which can be useful for
  • reordering the matrix based on the expression of a gene, then labeling cells with high expression of the gene via zooming
  • zooming into a section of the heatmap and labeling both rows/cols
  • linking to enrichment analysis results from Enrichr such that the genes associated with a specific term are highlighted
• clicking on a row/column label should allow the user to edit the manual categories of that specific row/column
• editing the manual category should automatically update the associated metadata (should not require running net.get_manual_category()) - I think this can be done using a on change widget method on the Python back-end
  • enable for row categories

Describe the solution you'd like
Mostly outlined above

Describe alternatives you've considered
None

Additional context
None