Reorganize and make X smaller

The x was too large, so I've shrunk it down to be smaller. In addition, I moved
the heatmap setup code around so that it is in one spot.
Annoying space removed
Add a grid to exemplar table

It's nice to show a grid to make things clearer when dealing with the exemplar
table.
Add hover to show we have no 3D

Now we add a simple hover that shows information when hovering over an exemplar
that does not have a structure. The hover only shows up in the sequence cell
which is what contains the sequence and warning symbol.