EntityResolver implementation for the Spring beans DTD,
to load the DTD from the Spring class path (or JAR file).
Fetches "spring-beans-2.0.dtd" from the class path resource
"/org/springframework/beans/factory/xml/spring-beans-2.0.dtd",
no matter whether specified as some local URL that includes "spring-beans"
in the DTD name or as "http://www.springframework.org/dtd/spring-beans-2.0.dtd".
Fetches "spring-beans-2.0.dtd" from the class path resource "/org/springframework/beans/factory/xml/spring-beans-2.0.dtd", no matter whether specified as some local URL that includes "spring-beans" in the DTD name or as "http://www.springframework.org/dtd/spring-beans-2.0.dtd".