Add ofType rxjs operator

[the-dr-lazy]

In redux-observable there is an operator that is a higher order operator for the filter operator but it only can get an action type and doesn't work with action creators. In deox we should export an operator for this job that works correctly with both action type, action and action creator.

Possible Implementation

import { filter } from 'rxjs/operators'

const ofType = <TC extends ActionCreator | AnyAction | string>(typeContainer: TC) => {
  const targetType = typeof typeContainer === 'string' ? typeContainer : getType(typeContainer)

  return filter(({ type }) => type === targetType)
}

[irmantaszenkus]

Is adding rxjs as a dependency brings value to this project? Maybe it could come as a separate package like deox/ofType?