More ergonomic handing of Unicode strings

[simonw]

It would be nice if you didn't have to manually convert to and from byte strings every time you use this library.

[simonw]

A .read_text(...) similar to in pathlib would be nice.

[simonw]

The .write(...) methods could take either bytes or str and encode as utf8 automatically.

[simonw]

This code here could use utf8 encoding when sending large Unicode strings, avoiding the extra overhead of base64:

github-contents/github_contents.py

Lines 102 to 109 in a125e53

	created_blob = self.session.post(
	self.base_url() + "/git/blobs",
	json={
	"encoding": "base64",
	"content": base64.b64encode(content_bytes).decode("latin1"),
	},
	headers=self.headers(),
	).json()