Add object arg overloads to Fmt to avoid params object[] allocation

Author: mythz

src/ServiceStack.Text/StringExtensions.cs

@@ -442,6 +442,21 @@ public static string Fmt(this string text, params object[] args)
             return String.Format(text, args);
         }
 
+        public static string Fmt(this string text, object arg1)
+        {
+            return String.Format(text, arg1);
+        }
+
+        public static string Fmt(this string text, object arg1, object arg2)
+        {
+            return String.Format(text, arg1, arg2);
+        }
+
+        public static string Fmt(this string text, object arg1, object arg2, object arg3)
+        {
+            return String.Format(text, arg1, arg2, arg3);
+        }
+
         public static bool StartsWithIgnoreCase(this string text, string startsWith)
         {
             return text != null