Guard for empty value elements
Correct whitespace
Handle empty <values> in `parseNode`, also arrays

The previous commit only handled structs, but conceivably array <values>
could be empty as well
Add tests for empty <values>
Some compressors get picky about int/double
Minify the source
Version bump
Parse <value> nodes as per spec

The spec says that childless <value> nodes should be treated as <string>
nodes. The text content of the <value> node should be the value.