Implementation of Tizen SSO APIs

Implementation of SSO APIs as per widl file https://code.google.com/p/accounts-sso/source/browse/widl/signon.widl?repo=libgsignon-glib

Backend that provides core functionality is gSSO and more information about that
component could be found at https://01.org/gsso
Not exactly, I suggest you read effective STL, `empty()` is always prefertered than `size() == 0`, stack overflow also has that conversation, http://stackoverflow.com/questions/743197/size-vs-empty-in-vector-why-empty-is-preferred