#22 Suggested change to project xml format for ids.

[Erik Shreve]

It is great that the project files use GUIDs for the element IDs. However, it would be better to store the IDs as attributes of the node rather than elements.

Here are some good guides on elements vs attributes for XML:
http://www.ibm.com/developerworks/library/x-eleatt/
http://www.w3schools.com/xml/xml_attributes.asp

In general, meta-data (such as ID) is best stored in attributes.