Save category description in Moodle XML import/export

What is not saved?

Some things are not saved At this format of import/expor:

1. description of the exported category,

2. description of parent category.

Current XML structure

If current category has not parent then

<question type="category">
  <category>
    <text>$course$/$category$</text>
  </category>
</question>

else

<question type="category">
  <category>
    <text>$course$/$parent$/$category$</text>
  </category>
</question>

Proposed XML structure

If the category has not parent then

<question type="category">
  <category>
    <name>
      <text>$category$</text>
    </name>
    <description>
      <text>Description of category</text>
    </description>
  </category>
</question>

else

<question type="category">
  <category>
    <name>
      <text>$parent$</text>
    </name>
    <description>
      <text>Description of category</text>
    </description>
    <category>
      <name>
        <text>$category$</text>
      </name>
      <description>
        <text>Description of category</text>
      </description>
    </category>
  </category>
</question>

Old export compatibility problem

The proposed structure is not compatible to the old.

I consider that proposed structure is possible to use as an independent format.