Preview demo for ESGF2

[johnkit]

The dataset in our ESGF example contains 420 relatively low-res 2D grids (432 x 324) representing each day from 2000-04-01 to 2001-05-31. There is one variable of interest "sfcWind" which represents near-surface wind speed.

It is currently configured for our poor-man's cube display, which is slow and underwhelming. Let's start by merging #103 to display as 2D vs time in the dataset viewer so that we are at least interactive.

[johnkit]

Cannot load ESGF example. Errors detailed in #102

[johnkit]

I think the number 1 thing we need here is an easier-to-use time widget. IIRC, the dataset has 420 time steps, 1 per day from April 2000 to May 2001. Starting with Seb's timeController.py example we should create a UI with 2 sliders to select the time step:

1. Month slider
2. Day-of-month slider

[johnkit]

Live with current time select.
Do something about scalar bar overlapping data.

[johnkit]

Replaced by #86