Make classpath for Spring ApplicationContext configurable

Issue #100 resolved
Sheila Morrissey
created an issue

org.jhove2.config.spring.SpringConfigInfo sets a the classpath search string with a static final string variable -- this search string is used to set the ApplicationContext, which in turn is used by various factory methods that invoke the static getContext() method in this class (either directly or indirectly) This creates a problem with the unit tests, which lose control of configuration (set in various config.xml files in src/test/resources) -- as those configuration settings are ignored in favor of settings in config/spring.