Extractor: Create and use wrapper for TumblrAPI

[syeopite]

Sometimes Tumblr's official client uses weird ways to request certain data.

For example for post reblog notes, the reblogs only filter will request an entirely different endpoint from the other filters.

Not to mention the weird route names they use.

Implementing all this behavior into the route logic complicates things and makes maintenance harder.

We should create and use a wrapped version of TumblrAPI that implements these unique behaviors and simplifies the method names for understanding.

Example of what the wrapper could do:

hubs_timeine --> get_tagged_posts
blog_posts(...) --> get_blog_posts
blog_posts(... tag="example") --> get_tagged_posts_from_blog