upnp/pupnp: request all mapping remove on IGD discovery

Send a request to delete all mappings created by previous
JAMI instances as soon as a new upnp IGD is discovered.
This is necessary with some implementations since they may
not respond well if the list of existing mappings is large.
Also make new requests for mappings with failing states.

Change-Id: I97308f1620128a63f111bcfc02122b472def5c85
Gitlab: #335