code: public static boolean deregisterDiagnosticModule(String packageName) {
          if (modules.containsKey(packageName)) {
              modules.remove(packageName);
              return true;
          } else
              return false;
      }
docs: Deregister a diagnostic module for a package
  
  @param packageName
  The package name for which to deregister a diagnostic module
  @return true if a diagnostic module was registered from the package (and
  is now not registered), false otherwise