✨🐱✨ smol - minimising imports!! #124

$ grep "^import" ./src/hip/* -h | sort | uniq
import contextlib   # *snip* (Used in the timeouts. Use an explicit manager instead.)
import contextvars  # *snip* (Used in the timeouts. An explicit style would be `backend.timeout(...)` instead of global contextvar.)
import copy         # *snip* (Used in JSON to ensure immutability. Easy to do this explicitly instead.)
import datetime     # *snip* (User in Server for `Date` header. Replace with `time.gmtime()` and an explicit formatting helper function)
import enum         # *snip* (Used in parsers. Could just use CONSTANTS.)
import io
import ipaddress    # *snip* (Used in URL parsing. This validation could be optional, or removed.)
import json
import logging      # *snip* (We could shim this.)
import os
import re
import time
import types        # *snip* (Annotations only.)
import typing       # *snip* (Annotations only.)
import zlib