More XML formats

Added support for wikimedia-web-apis of wikipedia and wikivoyage

Example: this query asks the german wikivoyage.org for entries around "Las Palmas, Gran Canaria"

• https://de.wikivoyage.org/w/api.php?action=query&format=xml&prop=coordinates|info|pageimages&inprop=url&piprop=thumbnail&generator=geosearch&ggscoord=28.12722|-15.43139&ggsradius=10000&ggslimit=5&pilimit=5

In general wikimedia looks like this

<api ...><query><pages>
    <page pageid='7445' title='Las_Palmas' touched='2015-02-10T08:04:45Z' fullurl='https://de.wikivoyage.org/wiki/Las_Palmas'>
        <coordinates><co lat='52' lon='9'/></coordinates>
        <thumbnail source='theIconUrl' width='50' height='38'/>
    </page>
</pages></query></api>

k3b-geoHelper will extract a poi-marker for every page element.