code: public ZipFileBuilder addClasspathResource(final String zipEntryPath, final String pathToResource) {
  
          final Class<?> callerClass = getCallerClass();
          final URL resource = resolver.resolve(pathToResource, callerClass);
          addResource(zipEntryPath, resource);
          return this;
      }
docs: Adds an entry to the zip file from a classpath resource.
  
  @param zipEntryPath
  the path of the entry in the zip file. If the path denotes a path (ends with '/') the resource is put
  under its own name on that location. If it denotes a file, it will be put as this file into the zip. Note
  that even if the path ist defined absolute, starting with a '/', the created entry in the zip file won't
  start with a '/'
  @param pathToResource
  the path to the resource in the classpath
  
  @return this builder