Changelog:
==========
Fix mixed content extension without explicit mixed attribute (issue #334)
Refine string serialization of XML resources and data elements
Switch to use elementpath v4
Fix sequence_type property for XSD types
Remove XsdElement.get_attribute(): unused and doesn't work as expected
Signed-off-by: Wang Mingyu <wangmy@fujitsu.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
