* remove obsolete files
* rename ttx-provider-nos-teletekst.c --> ttx-provider-nos-nl.c
* add support for provider-type-2, use e.g. by YLE
* make provider-ids strings
* ttx_provider_nos_teletekst => ttx_provider_nos_nl
* ttx-window: add combo box to choose between providers
* provider-ids are strings now
* configure: require gio
* providers/Makefile.am: add YLE
* add providers/ttx-providers-yle-fi
* ttx-window: fix switching between different providers
* cosmetics
* ttx-http: fix leak