public static SimpleTaskExecution of (String aKey, Object aValue) {
    return new SimpleTaskExecution(Collections.singletonMap(aKey, aValue));
  }
Creates a {@link SimpleTaskExecution} instance for the given 
Key-Value pair.

@return The new {@link SimpleTaskExecution}.
src/main/java/com/creactiviti/piper/core/task/SimpleTaskExecution.java