refactor connectThis

[yi-bai]

point: state.this and dispatch.this is not enough.
add a rewpa-thunk to getState via getState.this

[yi-bai]

see #19

[yi-bai]

current solution not work with redux-thunk

[yi-bai]

1. mapStateToProps(state, { path }) -> use rewpa.get(state, path) to get state of this scope.
2. mapDispatchToProps(dispatch, { path }), dispatch({ path, type:, payload: }) to dispatch to this scope.
3. write a middleware to change {path, type, payload} into {type, payload}