<para>
This option specifies the version of the GPX specification to use for
output.  The default version is 1.0 unless one or more of the input files
is GPX 1.1, then it's 1.1.  The only other valid value for this
option is 1.1.
</para>
<para>
Notice that this is not a full scale XML schema conversion.  In particular,
if you have a GPX 1.0 file that has extended namespaces in it (such as a
pocket query from Geocaching.com) just writing it with this option will
result in a horribly mangled GPX file as we can't convert the schema data.
</para>
