This patch set adds the basic support for OpenSSL crypto engine and async mode.
Changes since V2: - support keyword "algo" - ensure SSL engines are initialized before loading certs. - limit one async fd per SSL connection - better integrate with event cache Changes since V1: - add multiple engine support - allow default algorithms to be specified for an engine - remove the support for engine identifier "all" since (a) it is not possible to specify default algorithms for all engine and (b) "all" makes it hard to figure out what engine does what crypto algorithms. - address Willy's other comments.
