Improve interface of XMLClassDescriptorResolver(Impl)

Add the following methods

/**

• {@inheritDoc}
  */
  public void addClass(final String className) throws ResolverException { // _descriptorCache.loadCDRList(className, _loader); }
  
  /**
  * {@inheritDoc}

  */
  public void addClasses(final String[] classNames) throws ResolverException

  { // _descriptorCache.loadCDRList(className, _loader); }

/**

• {@inheritDoc}
  */
  public void addPackage(final String packageName) throws ResolverException { _descriptorCache.loadCDRList(packageName, _loader); }
  
  /**
  * {@inheritDoc}

  */
  public void addPackages(final String[] packageNames) throws ResolverException

  Unknown macro: { for (int i = 0; i < packageNames.length; i++) { _descriptorCache.loadCDRList(packageNames[i], _loader); } }

and deprecate loadClassDescriptors(String packageName) in order to increase readability et alias, ease of use