Modified check in _parse to accept relative URI
When using a path like '/tracks/current.gpx' the new check from #4 did expect it to be XML data but instead the data needs to be loaded with _load_xml. XML Data has to start with a lower than character now.
Merge pull request #6 from quelbs/master

Modified check in _parse to accept relative URI

Signed-off-by: Maxime Petazzoni <maxime.petazzoni@bulix.org>