Polish SSL certificate error handling

Polish SSL certificate error handling

This patch
- Adds SQUID_X509_V_ERR_DOMAIN_MISMATCH to TheSslErrorArray and in
  errors/templates/error-details.txt template file to enable bypass and
  details reporting for that error.

- Fixes the ssl error details handling code, to report the first honored error
  in a certificate, not the first certification validation error (which could
  have been bypassed).

- Adjust ssl_verify_cb() to copy ctx->error to error_no in the beginning and
  never use ctx->error after that.