[Patch draft] save conflicts to file

[bastiK]

It should be possible to save the conflicts of a data layer to a file.

The easiest way would be to include conflict data in the corresponding .osm file.

[bastiK]

A first draft is in conflict-save-draft01.patch​ (only node conflicts).

The format looks like this:

<?xml version='1.0' encoding='UTF-8'?>
<osm version='0.6' upload='false' generator='JOSM'>
  <bounds minlat='53.8750344' minlon='10.7050395' maxlat='53.8750914' maxlon='10.7051361' origin='CGImap 0.0.2'/>
  <node id='318023815' action='modify' timestamp='2012-09-05T19:45:18Z' uid='624553' user='triazone' visible='true' version='2' changeset='13000941' lat='53.8750642' lon='10.7050832'>
    <tag k='amenity' v='post_box'/>
    <tag k='brand' v='Deutsche Post'/>
    <tag k='collection_times' v='Mo-Fr 15:00,16:45;Sa 10:30'/>
    <tag k='operator' v='Post'/>
    <tag k='ref' v='Roeckstr.39/Rabenhorst, 23568 Lübeck'/>
    <conflict>
      <node id='318023815' timestamp='2012-09-05T19:45:18Z' uid='624553' user='triazone' visible='true' version='3' changeset='13000941' lat='53.8750642' lon='10.7050832'>
        <tag k='amenity' v='post_box'/>
        <tag k='brand' v='Deutsche Post'/>
        <tag k='collection_times' v='Mo-Fr 15:00,16:45;Sa 10:30'/>
        <tag k='operator' v='Deutsche Post'/>
        <tag k='ref' v='Roeckstr.39/Rabenhorst, 23568 Lübeck'/>
      </node>
    </conflict>
  </node>
</osm>