Add documentation for EzTemplate

[jypeter]

The only place where Google can find a reference to the nice EzTemplate module is the Polar Plots demo, where the module is used, with no users' manual on the web site!

It would be useful to have some form of https://github.com/CDAT/cdat-old-site/blob/master/eztemplate.md back on the current web site, with some links to find it easily

[doutriaux1]

@jypeter it used to be in the gallery. I will revive it today as a notebook.

[doutriaux1]

@jypeter see: https://github.com/CDAT/vcsaddons/blob/cleanup_eztemplates/Doc/Jupyter/Ez%20Templates.ipynb and #158

[doutriaux1]

Should be online at https://cdat.llnl.gov shortly

[jypeter]

@doutriaux1 when I'm on the Tutorials page, there is a placeholder for Easily create templates for VCS plots, but it's blank, and the link is dead when I click it

[jypeter]

Closing this, because I can indeed see the notebook in the tutorials