[CXF-5750,CXF-5751] - Support SpnegoContextTokens with the TransportBinding, Support policy validation for SupportingToken SpnegoContextTokens

Conflicts:
	rt/ws/security/src/main/java/org/apache/cxf/ws/security/wss4j/policyhandlers/AbstractBindingBuilder.java
	rt/ws/security/src/main/java/org/apache/cxf/ws/security/wss4j/policyvalidators/ConcreteSupportingTokenPolicyValidator.java
	rt/ws/security/src/main/java/org/apache/cxf/ws/security/wss4j/policyvalidators/EncryptedTokenPolicyValidator.java
	rt/ws/security/src/main/java/org/apache/cxf/ws/security/wss4j/policyvalidators/EndorsingEncryptedTokenPolicyValidator.java
	rt/ws/security/src/main/java/org/apache/cxf/ws/security/wss4j/policyvalidators/EndorsingTokenPolicyValidator.java
	rt/ws/security/src/main/java/org/apache/cxf/ws/security/wss4j/policyvalidators/SignedEncryptedTokenPolicyValidator.java
	rt/ws/security/src/main/java/org/apache/cxf/ws/security/wss4j/policyvalidators/SignedEndorsingEncryptedTokenPolicyValidator.java
	rt/ws/security/src/main/java/org/apache/cxf/ws/security/wss4j/policyvalidators/SignedEndorsingTokenPolicyValidator.java
	systests/ws-security/src/test/java/org/apache/cxf/systest/ws/spnego/SpnegoTokenTest.java
	systests/ws-security/src/test/resources/org/apache/cxf/systest/ws/spnego/DoubleItSpnego.wsdl
	systests/ws-security/src/test/resources/org/apache/cxf/systest/ws/spnego/client.xml
	systests/ws-security/src/test/resources/org/apache/cxf/systest/ws/spnego/server.xml
	systests/ws-security/src/test/resources/org/apache/cxf/systest/ws/spnego/stax-server.xml
Recording .gitmergeinfo Changes
Fixing build