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
As per https://gcc.gnu.org/onlinedocs/libstdc++/libstdc++-html-USERS-4.1/stl__tree_8h-source.html
there is no difference in empty and size() ... so both are same ... or even now u think it should be same..
00629       bool
00630       empty() const
00631       { return _M_impl._M_node_count == 0; }
00632 
00633       size_type
00634       size() const
00635       { return _M_impl._M_node_count; }