Replace console.assert() with Facebook's invariant

[tkrotoff]

See https://github.com/zertosh/invariant
See https://github.com/facebook/fbjs/blob/c69904a511b900266935168223063dd8772dfc40/packages/fbjs/src/__forks__/invariant.js

[tkrotoff]

See https://github.com/BerkeleyTrue/warning, used by Material-UI: https://david-dm.org/mui-org/material-ui?path=packages%2Fmaterial-ui

[tkrotoff]

The real issue is here: https://github.com/tkrotoff/react-form-with-constraints/blob/v0.12.0/packages/react-form-with-constraints/src/FormWithConstraints.tsx#L113

The console.assert() here can make user tests fail.

[tkrotoff]

See 340db73, packaged with v0.13.0