Reverting mysql to 2.1.1

I am currently doing some testing on this but I believe it is fine with knex 0.7.3

- Unfortunately mysql has changed the way it handles the charset setting such that
it now causes encoding issues on many setups where 'utf8' is apparently not the
correct setting.
- We need to revert this upgrade until the issue is fixed or we have a way to handle
it nicely for our users.