[x] Change animation return type [x] Fix types [ ] Add unsubscribe fns to primitives lib [ ] Swap out setInterval in primitives lib [ ] Fix remaining type errors with router lib bindings [ ] Fix memory leak [ ] Finish PR in router primitives with changes [ ] Breakout into 2 libraries [ ] Publish router-primitives-react lib [ ] Write readme docs [ ] Publish animated components lib [ ] Add CSS support