Single cell browser component (#819)

* starting component

* further buildout of components

* fixing v-key errors

* Single Cell Browser component(s)

* adding hover labels to umap buttons and 'colo by' labels

* add umap tooltip for zoom/pan

* data cleanup fix

* starting select component for single cell browser color picker

* cfde citation formatting

* adding support for query string params

* adding layouts + more

* single cell plot updates