m_ssl_gnutls Re-set DH params when the gnutls_certificate_credentials_t struct is reallocated
Fix an off-by-one on registration timeout handling.

The use of > instead of >= here added a second onto the configured timeout.

We won't be breaking any existing configuration, because users.h explicitly
increases the limit if it's 0.
Merge pull request #929 from rburchell/insp20

Fix an off-by-one on registration timeout handling.