doc: Correct comment about ignoring certs in the SRP server example

Point readers to another example for a way to validate certificates in
both the SRP and the X.509 server example

Signed-off-by: Attila Molnar <attilamolnar@hush.com>
doc: Explain post-callback deallocation behavior for the SRP server callback

Signed-off-by: Attila Molnar <attilamolnar@hush.com>
doc: more consistent use of pointer star.
gnutls-cli: Do not try to load the system CA trust if --insecure is specified.
clarified license text
updated thanks file