#24 Display icon for federated contacts (application/pidf+xml)

[pier eleven]

PIDF format, used to represent status of federated (AOL, MSN) contacts, contains a valid URL to the network icon.
It make sense to display it as a buddy icon in SIPE if possible.

Live application/pidf+xml examples containing the icon URL (open the URL in browser to see):
AOL:
<presence xmlns="urn:ietf:params:xml:ns:pidf" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ep="urn:ietf:params:xml:ns:pidf:status:rpid-status" xmlns:rpid="urn:ietf:params:xml:ns:pidf:rpid" xmlns:ci="urn:ietf:params:xml:ns:pidf:cipid" xsi:schemaLocation="urn:ietf:params:xml:ns:pidf pidf.xsd urn:ietf:params:xml:ns:pidf:data-model data-model.xsd urn:ietf:params:xml:ns:pidf:rpid rpid.xsd" entity="user3@aol.com" >
<tuple id="0" >
<status>
<basic>open</basic>
<rpid:user-input>active</rpid:user-input>
</status>
</tuple>
<ci:icon>http://www.aimatwork.com/ms/icons/aim.png</ci:icon>
</presence>

AOL:
<?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ep="urn:ietf:params:xml:ns:pidf:status:rpid-status" xmlns:rpid="urn:ietf:params:xml:ns:pidf:rpid" xmlns:ci="urn:ietf:params:xml:ns:pidf:cipid" xsi:schemaLocation="urn:ietf:params:xml:ns:pidf pidf.xsd urn:ietf:params:xml:ns:pidf:data-model data-model.xsd urn:ietf:params:xml:ns:pidf:rpid rpid.xsd" entity="user1@aol.com" >
<tuple id="0" >
<status>
<basic>open</basic>
<rpid:user-input>active</rpid:user-input>
</status>
</tuple>
<ci:icon>https://components.premiumservices.aol.com/images/aim.png</ci:icon>
</presence>

MSN:
<?xml version="1.0" encoding="UTF-8"?>
<presence xmlns="urn:ietf:params:xml:ns:pidf" xmlns:ep="urn:ietf:params:xml:ns:pidf:status:rpid-status" xmlns:et="urn:ietf:params:xml:ns:pidf:rpid-tuple" xmlns:ci="urn:ietf:params:xml:ns:pidf:cipid" entity="sip:user3(some.net)@msn.com">
<tuple id="0">
<status>
<basic>closed</basic>
</status>
</tuple>
<ci:icon>https://images.edge.messenger.live.com/Messenger_16x16.png</ci:icon>
<ci:display-name>user3@some.net</ci:display-name>
</presence>