Refs #595: If a user is already logged in, and we're not changing user, don't revalidate their hmac
Closes #595: Introducing cookie_jar configuration directive; web service calls now use a per user cookie jar for all requests.
Merge branch 'master' into fixing-signedhttp-api

Conflicts:
	Idno/Core/Config.php
Merge branch 'master' into fixing-signedhttp-api

Conflicts:
	Idno/Core/Webservice.php
Merge pull request #596 from mapkyca/fixing-signedhttp-api

Fixing signedhttp api