Allow for custom configuration of authorization service for publishing operations

[LucaCinquini]

Who: Zed

Zed reported that after a standard installation, their publishing operations fail because of the following setting in the application.properties file:

URL of authorization service used to authorize publishing operations
security.authz.service.endpoint=https://localhost/esg-orp/saml/soap/secure/authorizationService.htm

which should instead contain the hostname of the server.

[LucaCinquini]

That value is passed to the SAMLAuthorizer through this setting in the security-context.xml:

<bean name="authorizer" class="esg.orp.app.SAMLAuthorizer">
    <property name="endpoints">
            <value>${security.authz.service.endpoint}</value>
    </property>
</bean>

The SAMLAuthorizer probably needs to change to use the ESGFProperties class and read the value of the property at a specified key.