New CL Argument

[zanderlewis]

What if we add a elide previous or something similar to revert back to a previous version of Elide? Elide is unstable and still in alpha and this feature could be useful when an update has a breaking change.

[sgammon]

There is a selfupdate command, but I don't know if it accepts an explicit version yet. That's a good idea. It should be easy to change versions of Elide as needed at least until it is stable.