Keychain 3.0.0 beta3

Third public beta of Keychain 3.x, collecting changes made after the
3.0.0_beta2 tag.

This release focuses on feature additions and robustness. It makes Keychain
more dependable during shell startup, easier to configure,
supports smartcards or other PKCS#11-backed SSH tokens, closes
a known .keychainrc documentation gap, and significantly enhances
the integrated documentation and documentation rendering.

Highlights:

• More reliable agent startup. Keychain now keeps its managed ssh-agent
  socket in a stable location under ~/.keychain/ instead of depending on
  temporary /tmp/ssh-* paths. This helps avoid cases where the agent is
  still running but its socket directory has been cleaned up, a problem that
  showed up clearly under WSL but is not unique to it.

• Better smartcard and hardware-token support. You can now ask Keychain to
  load a PKCS#11 provider directly with pkcs11:/path/to/provider.so. This is
  useful for SSH keys stored on smartcards, security keys, and similar devices.
  This addresses issue #216.

• Improved Documentation Formatting. Significant improvements in the
  embedded documentation renderer used by keychain man. Pager support
  integrated. Supported .keychainrc config settings are now fully
  documented, streamlined and available. Addresses issue #217.

• Improved 2.9.8 compatibility details. A few legacy command-line edge
  cases with --stop and --wipe now print a more accurate error message.

• Copyright has been updated to reflect assignment/ownership by Daniel
  Robbins, the person, removing reference to BreezyOps / Funtoo Solutions,
  Inc.