remove case sensitivity from swarm plot gene highlight and add cell search component in heatmap

[valearna]

In the Swarm Plot panel of Wormcells-viz, the "Select Genes to Highlight" search bar could be more useful without case sensitivity conditions. (Allow to pop up the corresponding gene regardless of Letter case in search bar). One could do the same for the Cells search bar in the Gene Expression Heatmap panel.

[Munfred]

Seems to be working at http://cervino.caltech.edu:3000/swarm