Deprecate SAML assertionConsumerIndex config property

[hsinn0]

• It only works if set to 0, which is the default value for the optional parameter.

When the property was set to 1, UAA tried to use URI binding as expected per the SAML SP metadata. However, it failed with exception as URI binding is not supported by the saml library, as follows:

ERROR --- SecurityFilterChainPostProcessor$HttpsEnforcementFilter: Uncaught Exception:
javax.servlet.ServletException: org.opensaml.saml2.metadata.provider.MetadataProviderException: Endpoint designated by the value in the WebSSOProfileOptions is not supported by this profile
        at org.cloudfoundry.identity.uaa.provider.saml.LoginSamlEntryPoint.commence(LoginSamlEntryPoint.java:70) ~[cloudfoundry-identity-server-0.0.0.jar:?]
...
Caused by: org.opensaml.saml2.metadata.provider.MetadataProviderException: Endpoint designated by the value in the WebSSOProfileOptions is not supported by this profile
        at org.springframework.security.saml.websso.WebSSOProfileImpl.getAssertionConsumerService(WebSSOProfileImpl.java:180) ~[spring-security-saml2-core-1.0.10.RELEASE.jar:1.0.10.RELEASE]
        at org.springframework.security.saml.websso.WebSSOProfileImpl.sendAuthenticationRequest(WebSSOProfileImpl.java:90) ~[spring-security-saml2-core-1.0.10.RELEASE.jar:1.0.10.RELEASE]
        at org.springframework.security.saml.SAMLEntryPoint.initializeSSO(SAMLEntryPoint.java:225) ~[spring-security-saml2-core-1.0.10.RELEASE.jar:1.0.10.RELEASE]
        at org.cloudfoundry.identity.uaa.provider.saml.LoginSamlEntryPoint.commence(LoginSamlEntryPoint.java:61) ~[cloudfoundry-identity-server-0.0.0.jar:?]
        ... 102 more

[duanemay]

LGTM