Improve chart / table switching
Improve chart / table switching

Previously the switching would work, but the icons would not
update. Now we add or remove the `active` class as necessary.

I tried doing this via `modelEvents: { 'change:mode': 'render' }`,
but that would get rid of the precipitation control added in
`onShow`. This seemed like the best second option.

WikiWatershed/model-my-watershed,WikiWatershed/model-my-watershed,WikiWatershed/model-my-watershed,WikiWatershed/model-my-watershed,WikiWatershed/model-my-watershed