Cleaned XML and examples plus some minor additions to XSD

SI_Format.xsd

examples/BRONZE/2020-03-20-UM-BRONZE-examples.xml

examples/BRONZE/2021-11-22-BRONZE-examples-xmllists.xml

examples/BRONZE/2022-05-23-BRONZE-examples.xml

examples/BRONZE/PTB-BRONZE-examples-2.xml

examples/BRONZE/PTB-BRONZE-examples.xml

examples/GOLD/2020-03-20-UM-GOLD-examples.xml

examples/GOLD/2021-10-26-GOLD-examples-xmllists.xml

examples/GOLD/2022-05-23-GOLD-examples.xml

examples/GOLD/PTB-GOLD-examples-2.xml

examples/GOLD/PTB-GOLD-examples.xml

examples/GOLD/gold-test.xml

examples/IMPROVABLE/2020-03-20-UM-IMPROVABLE-examples.xml

...es/IMPROVABLE/2021-11-23-IMPROVABLE-examples-xmllists.xml

examples/IMPROVABLE/2022-05-23-IMPROVABLE-examples.xml

examples/IMPROVABLE/PTB-IMPROVABLE-examples-2.xml

examples/IMPROVABLE/PTB-IMPROVABLE-examples.xml

examples/IMPROVABLE/improvable-test.xml

examples/NOT PASSED/UM58-D-SI-example.xml

examples/NOT PASSED/UM59-D-SI-example.xml