refactor: rework imports across code base

* Update to import from rxjs when required
* Reorder imports to adhere to the angular styleguide:
external imports first, followerd by a line break and the local imports

Author: FIXED-TERM Toledo Navarro Jose Ignacio (BueP/ICO)

src/factory.ts

@@ -1,7 +1,8 @@
 import { Action } from '@ngrx/store';
+import { materialize } from 'rxjs/operators';
+
 import { NGRX_ACTIONS_META, StoreMetadata } from './internals';
 import { NgrxSelect } from './select';
-import { take, materialize } from 'rxjs/operators';
 
 export function createReducer<TState = any>(
   store:

src/module.ts

@@ -1,6 +1,7 @@
 import { NgModule, InjectionToken, ModuleWithProviders, Injector, Inject, Optional } from '@angular/core';
-import { NgrxSelect } from './select';
 import { Store, StoreModule, ReducerManager, combineReducers } from '@ngrx/store';
+
+import { NgrxSelect } from './select';
 import { createReducer } from './factory';
 
 export const STORE_TOKEN = new InjectionToken<any>('STORE_TOKEN');

src/of-action.ts

@@ -1,6 +1,7 @@
 import { Action } from '@ngrx/store';
 import { filter } from 'rxjs/operators';
-import { OperatorFunction } from 'rxjs/interfaces';
+import { OperatorFunction } from 'rxjs';
+
 import { ActionType } from './symbols';
 
 export function ofAction<T extends Action>(allowedType: ActionType<T>): OperatorFunction<Action, T>;

src/spec/index.spec.ts

@@ -1,7 +1,7 @@
-import { Store, createReducer, Action, ofAction, Select, NgrxSelect } from '../index';
 import { Action as NgRxAction, createFeatureSelector, createSelector, Store as NgRxStore } from '@ngrx/store';
-import { Observable } from 'rxjs/Observable';
-import { of } from 'rxjs/observable/of';
+import { Observable, of } from 'rxjs';
+
+import { Store, createReducer, Action, ofAction, Select, NgrxSelect } from '../index';
 
 describe('actions', () => {
   interface FooState {