Itch-dl

- Fixed a crash while attempting to download access restricted title pages. They are currently not supported, but this allows downloading libraries or bundles with restricted items without crashing.

- Fixed crashes with `--mirror-web` being unable to parse the new timestamp format - thanks mlewisa for the bugfix!
- Added support for downloading My Purchases and Collections - thanks to triple-j for this change!
- Misc dependency and docs updates.

Apologies for updates being this slow, looks like I'm not handling this project very well...

- Enforce UTF-8 usage end-to-end to prevent garbled site mirrors (partially fixes 8)

- Add support for infobox "Code license" entries (closes 6)
- Open game jam JSON files in binary mode (thanks to jackwilsdon)

Forgot to git add a new source file to 0.3.0, this one's a bit more functional.

- Added [Settings](https://github.com/DragoonAethis/itch-dl/wiki/Configuration-Files) - it's now possible to permanently set an API key instead of providing it every single time on the command line. (Using the config file is not mandatory.)
- itch-dl now depends on Pydantic for config file validation.
- The User Agent is now being set to `python-requests/{version} itch-dl/{version}` by default. This is configurable.
- Misc cleanups, typing fixes and more descriptive error messages with wiki links.