SSL certificate handling in CMIS/AlfrescoSDK

* changed the name of the flag to be more indicative of what it actually does
* per default, the server is untrusted - unless a parameter is explicitly set
* the HTTP requests in both CMIS/Alfresco check the host name as well as the value of the flag (the one passed into Alfresco/CMIS session)

Note: I did deliberately not pull the authentication handling into the Alfresco Authentication Provider. I know this is how we do it in CMIS - however, it would mean a change in the public interface (AuthenticationProvider) and I wasn't sure whether we want to do it at this stage.

Samples apps have been updated with the latest code