Add async overload for columns+values insert

Author: Leon V

SqlKata.Execution/Query.Extensions.cs

@@ -168,6 +168,11 @@ public static int Insert(this Query query, IEnumerable<string> columns, IEnumera
             return CreateQueryFactory(query).Execute(query.AsInsert(columns, valuesCollection), transaction, timeout);
         }
 
+        public static async Task<int> InsertAsync(this Query query, IEnumerable<string> columns, IEnumerable<IEnumerable<object>> valuesCollection, IDbTransaction transaction = null, int? timeout = null)
+        {
+            return await CreateQueryFactory(query).ExecuteAsync(query.AsInsert(columns, valuesCollection), transaction, timeout);
+        }
+
         public static int Insert(this Query query, IEnumerable<string> columns, Query fromQuery, IDbTransaction transaction = null, int? timeout = null)
         {
             return CreateQueryFactory(query).Execute(query.AsInsert(columns, fromQuery), transaction, timeout);