Feature request: allow multiple mysql versions, just like with php and elastic search

[Evertt]

$ valet use mysql 5.7

$ valet use mysql 8.0

Why implement this feature?
Well because whenever I have the opportunity to start a project from scratch I like working with the latest technologies whenever possible, so then I would prefer working with MySQL 8.0. And other times I need to work with an older project that uses an older version of Laravel that only supports MySQL 5.7.

What will be required for this feature?
I don't really know. I'm assuming that when one switches from one version to the other, that we need to backup their databases and log files somewhere. And restore them whenever they switch back to that version.

Otherwise I don't really know what this entails.

[mischabraam]

https://gist.github.com/ivanvermeyen/c2dfb8ad55a4fb699c5913a09422c1d9