Declare height and width key element under graphml element

[agustinus-lawandy-systema]

When creating a GraphML from QVGE project. The node may contain custom data height and width.

  <node id="N2">
      <data key="height">9</data>
      <data key="width">11</data>
      <data key="x">75</data>
      <data key="y">-150</data>
  </node>

Thus it is expected that under <graphml> element there would be <key> with id height and width. But the node height and width keys doesn't exist.

<graphml xmlns="http://graphml.graphdrawing.org/xmlns" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://graphml.graphdrawing.org/xmlns http://graphml.graphdrawing.org/xmlns/1.0/graphml.xsd">

  <key id="x" attr.name="x" for="node" attr.type="float">
      <default>0</default>
  </key>
  <key id="y" attr.name="y" for="node" attr.type="float">
      <default>0</default>
  </key>
<!-- The rest is omitted for brevity... See the attached file -->

Additionally, when I added node height and node width manually in the GraphML file, the QVGE app treats it as a custom attribute and does not change the default value of attribute size (height, width) : 11x11