fix(Tag): fix state not matching props

[jdkahn]

• derive checked state from props

[codecov]

Codecov Report

Merging #614 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #614      +/-   ##
==========================================
+ Coverage   91.21%   91.21%   +<.01%     
==========================================
  Files         244      244              
  Lines       13889    13893       +4     
  Branches     4336     4337       +1     
==========================================
+ Hits        12669    12673       +4     
  Misses       1201     1201              
  Partials       19       19

Impacted Files	Coverage Δ
src/tag/selectable.jsx	100% <100%> (ø)	⬆️

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[youluna]

we need to import react-lifecycles-compat to make sure it can work on React v16.0-16.2
please run :
npm install --save react-lifecycles-compat

// add
import { polyfill } from 'react-lifecycles-compat';

class Selectable extends Component {
   ...
}
// add
polyfill(Selectable);

export default Selectable;