Update readme to include usage of the ExcelColumn attribute to map co…

…lumns.

readme.markdown

@@ -45,6 +45,20 @@ Column names from the worksheet can be mapped to specific property names on the
 	                       where c.State == "IN" && c.Employees > 500
 	                       select c;
 
+Column names can alternately be mapped using the **ExcelColumn** attribute on properties of the class.
+
+	public class Company
+	{
+		[ExcelColumn("Company Title")] //maps the "Name" property to the "Company Title" column
+		public string Name { get; set; }
+
+		[ExcelColumn("Providence")] //maps the "State" property to the "Providence" column
+		public string State { get; set; }
+
+		[ExcelColumn("Employee Count")] //maps the "Employees" property to the "Employee Count" column
+		public string Employees { get; set; }
+	}
+
 ## Using the LinqToExcel.Row class
 Query results can be returned as LinqToExcel.Row objects which allows you to access a cell's value by using the column name in the string index. Just use the **Worksheet()** method without a generic argument.