Downgrade packages

[frontowiec]

Why?

92b112a#diff-b9cfc7f2cdf78a7f4b91a753d10865a2

[VasilyShelkov]

This has caused an issue in particular with Jest going from 22.3.4 => 20.0.4 where https://jestjs.io/docs/en/jest-object#jestrestoreallmocks is not available in 20.0.4

[frontowiec]

Yes, I have same issue.
My tests are broken because jest.fn().mockName() is undefined.

Is the only solution is fix broken tests?

[VasilyShelkov]

I've just reverted until this gets sorted out or the major upgrade gets properly documented... I'm also expecting CRA 2.0 to get merged in somehow too so probably will wait until that to upgrade

[frontowiec]

So I'll wait for upgrade to CRA 2.0

@VasilyShelkov Thanks for the advice!