Use parse_headers for media endpoint uploads

micropub_media_post_for_user makes a case-sensitive search for the
Location header, which fails if the location header is all lowercase.

This change uses the `headers` fields, introduced in
2b98a4548e82f1133bf62918b0106ab99a21fa29a, to find the Location header,
regardless of case.

Fix reload targets

closes #112

🙈

the API dropped their free tier

remove trailing comma in sqlite schema

should help clear out the draft when a post is created.

for #109

now supports pkce

Simple Addition of Profile Data to Quill

still shows debug messages when missing endpoints to help people get started