VEDA Docs in instances doesn't update

[wildintellect]

The version of VEDA Docs cloned to users home directories doesn't update automatically. So it stays at whatever version was cloned at the time you launched your first Pangeo instance.

We either need to document this so users know they have to git pull if they want the latest docs, or we need a mechanism to refresh somehow.

Not Critical but something to think about.

cc: @yuvipanda @sunu @j08lue

[j08lue]

Took the liberty to transfer this issue here to JupyterHub.

I second the goal that users always have the latest veda-docs available in their container.

git pull will fail if users made changes in their copt of veda-docs that conflict with new upstream commits, or checked out another branch.

Ideally, the veda-docs copy included with the container would be read-only.