Errors in data source subsystem checking

1) it's possible to add <flush-strategy> element with any value (not only listed in xsd schema)

2) it's possible to add <xa-data-source> element without any <xa-datasource-property>(in xsd schema minOccurs=1)

3) it's possible to add 2 or more <security-domain> elements without error(in xsd schema maxOccurs=1)

4) it's impossible to add <datasource-class> element with any value except of INTEGER:
org.jboss.as.test.integration.management.util.MgmtOperationException: Management operation failed: {"JBAS014653: Composite operation failed and was rolled back. Steps that failed:" => {"Operation step-1" => "JBAS014749: Operation handler failed: For input string: \"DsClass\""}}
5) it's impossible to add a <driver> element without module attribute:
org.jboss.as.test.integration.management.util.MgmtOperationException: Management operation failed: {"JBAS014653: Composite operation failed and was rolled back. Steps that failed:" => {"Operation step-1" => "JBAS010441: Failed to load module for driver [undefined]"}}
6)it's possible to add 2 <driver-class> elements (maxOccur=1 in xsd)
7)it's possible to add 2 <xa-datasource-class> elements (maxOccur=1 in xsd)