proof_of_work 1.0.0-alpha1

First alpha release of Proof of Work.

Challenges

• SHA-256 puzzle: proof of work in a Web Worker (JavaScript).
• Shape matching: match shapes in order, without JavaScript (disabled by default).
• Waiting time: signed meta refresh, optionally in several steps, without JavaScript.

Highlights

• Stateless: HMAC-signed tokens and passes bound to the client IP address.
• Protected pages stay cacheable in the internal page cache.
• Optional Content-Security-Policy (csp module) nonce support.

This is an alpha release: APIs and configuration may still change. Feedback in the issue queue is welcome.