- Update to version 0.1.21:
* Only use `ifr_ifindex` if OS supports it, fixes build on iOS
and FreeBSD.
- Changes from version 0.1.20:
* Remove support for GStreamer 0.10 builds.
* Add macro to check LIBNICE version.
* Added utility function to get the STUN server from a candidate.
* Support additional header in built-in HTTP proxy client.
* Add boxed type for NiceAddress for bindings.
* Add API to get the interface index for a local address.
* Explicitly bind to a specific interface when creating UDP
sockets.
* Limit the number of stored incoming checks based on a property.
* Do asynchronous DNS resolution for STUN and TURN servers.
* Add introspection friendly API to get an allocated string from
a NiceCandidate.
* Enable gst-full to link in a single element.