def for(period=nil)
			if period.nil? or period == ""
				period = now.strftime(@format) if today_for_nil
				return period
			else
				translated = @translate.this period
 				@last_date = @date = time_for_period(translated)
				@date.strftime(@format) if @date.respond_to? :strftime
			end
		end
def for(period=nil)
			if period.nil? or period == ""
				period = now.strftime(@format) if today_for_nil
				return period
			else
				translated = @translate.this period
 				@last_date = @date = time_for_period(translated)
				@date.strftime(@format) if @date.respond_to? :strftime
			end
		end
Creates a Dater::Resolver object

 @param [String] format = date format
 @param [String] lang = languaje for matching (en=english, es=spanish, pt=portuguese)
 @param [Boolean] today_for_nil = Indicates if must return today's date if given argument is nil
 Convert the period of time passed as argument to the configured format

 @param [String] period = a period of time expreseed in a literal way to convert to the configured format (@format)
 @return [String] converted date to the configured format. If period is nil and @today_for_nil is true, returns date for tomorrow. Else returns nil