Adding "month" period

Modules/Common.pm

@@ -29,10 +29,11 @@ our %mktime_day = (
 # Périodes possibles
 our %periods = (
 	"minute" => 60,
-	"min"    => 60,
 	"hour"   => 60 * 60,
 	"day"    => 60 * 60 * 24,
 	"week"   => 60 * 60 * 24 * 7,
+	"month"  => 60 * 60 * 24 * 30,
+	"min"    => 60,
 	"m"      => 60,
 	"h"      => 60 * 60,
 	"d"      => 60 * 60 * 24,