Fix/#754

[hkurra]

• Made changes to run CustomPicker aka ColorWrap HoC in all version of React.

• Replaced getDerivedStateFromProps with componentDidUpdate and put a check on colour input props before updating color state

• [x] Ran npm run test and verified all test cases are getting passed

• [x] Ran npm run eslint and there was not any es-lint errors

• [x] Verified these changes in custom-picker example with both the latest(6.12.0) and old version (15.6.1) of react

[aelfric]

I think this might also fix #731 which was causing problems on a project I was trying to use this library in.

[adamborowski]

Hi. Any chance to get it merged and released soon?