Move all firbase dependencies from actions layer to firebaseService layer (#13)

app/services/posts/IPostService.ts

@@ -1,15 +1,16 @@
 import { User } from 'domain/users'
-
-
-
+import { Post } from 'domain/posts'
 
 /**
  * Post service interface
- * 
+ *
  * @export
  * @interface IPostService
  */
 export interface IPostService {
-
-
-}
+  addPost: (userId: string, post: Post) => Promise<string>
+  updatePost: (userId: string, postId: string, post: Post) => Promise<void>
+  deletePost: (userId: string,postId: string) => Promise<void>
+  getPosts: (userId: string) => Promise<{ [postId: string]: Post }>
+  getPostById: (userId: string, postId: string) => Promise<Post>
+}