You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <allimages aicontinue="Backmarker1_2015.jpg" />
  </query-continue>
  <query>
    <allimages>
      <img name="B11.png" timestamp="2016-01-04T12:59:40Z" url="https://www.gpvwc.com/wiki/images/0/0a/B11.png" descriptionurl="https://www.gpvwc.com/wiki/index.php?title=File:B11.png" ns="6" title="File:B11.png" />
      <img name="B21.png" timestamp="2016-01-04T13:03:03Z" url="https://www.gpvwc.com/wiki/images/9/9d/B21.png" descriptionurl="https://www.gpvwc.com/wiki/index.php?title=File:B21.png" ns="6" title="File:B21.png" />
      <img name="B31.png" timestamp="2016-01-04T13:05:04Z" url="https://www.gpvwc.com/wiki/images/8/80/B31.png" descriptionurl="https://www.gpvwc.com/wiki/index.php?title=File:B31.png" ns="6" title="File:B31.png" />
      <img name="BA_Racing_2000.png" timestamp="2011-12-02T17:03:26Z" url="https://www.gpvwc.com/wiki/images/6/62/BA_Racing_2000.png" descriptionurl="https://www.gpvwc.com/wiki/index.php?title=File:BA_Racing_2000.png" ns="6" title="File:BA Racing 2000.png" />
      <img name="BA_Racing_2002.png" timestamp="2011-11-30T17:42:32Z" url="https://www.gpvwc.com/wiki/images/7/78/BA_Racing_2002.png" descriptionurl="https://www.gpvwc.com/wiki/index.php?title=File:BA_Racing_2002.png" ns="6" title="File:BA Racing 2002.png" />
      <img name="BMW_K=Xtreme.jpg" timestamp="2015-07-09T13:45:07Z" url="https://www.gpvwc.com/wiki/images/3/3d/BMW_K%3DXtreme.jpg" descriptionurl="https://www.gpvwc.com/wiki/index.php?title=File:BMW_K%3DXtreme.jpg" ns="6" title="File:BMW K=Xtreme.jpg" />
      <img name="BMW_SimRace_SA_Livery2.jpg" timestamp="2015-07-09T13:33:32Z" url="https://www.gpvwc.com/wiki/images/9/9f/BMW_SimRace_SA_Livery2.jpg" descriptionurl="https://www.gpvwc.com/wiki/index.php?title=File:BMW_SimRace_SA_Livery2.jpg" ns="6" title="File:BMW SimRace SA Livery2.jpg" />
      <img name="BW_wip2.jpg" timestamp="2014-07-31T01:31:45Z" url="https://www.gpvwc.com/wiki/images/4/43/BW_wip2.jpg" descriptionurl="https://www.gpvwc.com/wiki/index.php?title=File:BW_wip2.jpg" ns="6" title="File:BW wip2.jpg" />
      <img name="BackMarker_Brigade_logo_2015.jpg" timestamp="2015-03-14T23:28:33Z" url="https://www.gpvwc.com/wiki/images/2/26/BackMarker_Brigade_logo_2015.jpg" descriptionurl="https://www.gpvwc.com/wiki/index.php?title=File:BackMarker_Brigade_logo_2015.jpg" ns="6" title="File:BackMarker Brigade logo 2015.jpg" />
      <img name="BackMarker_Brigadeside2.png" timestamp="2015-03-15T00:12:02Z" url="https://www.gpvwc.com/wiki/images/4/43/BackMarker_Brigadeside2.png" descriptionurl="https://www.gpvwc.com/wiki/index.php?title=File:BackMarker_Brigadeside2.png" ns="6" title="File:BackMarker Brigadeside2.png" />
    </allimages>
  </query>
</api>