code: public static <C> SLF4JLogTemplate<C> toSLF4J(String loggerName, String levelName) {
  		return toSLF4J(loggerName, levelName, null);
  	}
docs: Produces a concrete log template which logs messages into a SLF4J Logger.
  
  @param loggerName Logger name
  @param levelName Level name (info, debug, warn, etc.)
  @return Logger