v0.6.0

Changelog

• d666ed3 Posting review fixes: pin GitHub's diff options, stateful diff parser, clearer retries
• 801d977 Posting: UTF-8-safe reason, one length budget for the review body
• 541972b Posting: list out-of-diff comments in the body, keep GitHub's reason, retry transient failures (#14)
• fed2d1f approval tests: re-poll until the state arrives
• 877769f ghost review opens Ghost on that PR and reviews it (#15)
• 0e71662 ghost review: fetch the PR before the engine starts; guard the session tab's name
• 1c0de02 r confirms the review was queued and says why it's waiting (#9)
• 7c736c6 test: fail clearly if seeding the queued review fails