Merge branch 'devel-2.5'

* devel-2.5:
  Add tls_ciphers and use_vdagent options
  Updated man pages with new SPICE TLS options
  Implementation of TLS-protected SPICE connections
  Added SPICE TLS option and related cert paths
  Fix OS creation's error handling when pausing sync

Signed-off-by: Andrea Spadaccini <spadaccio@google.com>
Reviewed-by: Michael Hanselmann <hansmi@google.com>