add mysql impl for ICapTransaction

src/DotNetCore.CAP.MySql/ICapTransaction.MySql.cs

+using System.Data;
+using System.Diagnostics;
+using Microsoft.EntityFrameworkCore.Storage;
+
+// ReSharper disable once CheckNamespace
+namespace DotNetCore.CAP
+{
+    public class MySqlCapTransaction : CapTransactionBase
+    {
+        public MySqlCapTransaction(IDispatcher dispatcher) : base(dispatcher) { }
+
+        public override void Commit()
+        {
+            Debug.Assert(DbTransaction != null);
+
+            switch (DbTransaction)
+            {
+                case IDbTransaction dbTransaction:
+                    dbTransaction.Commit();
+                    break;
+                case IDbContextTransaction dbContextTransaction:
+                    dbContextTransaction.Commit();
+                    break;
+            }
+
+            Flush();
+        }
+
+        public override void Rollback()
+        {
+            Debug.Assert(DbTransaction != null);
+
+            switch (DbTransaction)
+            {
+                case IDbTransaction dbTransaction:
+                    dbTransaction.Rollback();
+                    break;
+                case IDbContextTransaction dbContextTransaction:
+                    dbContextTransaction.Rollback();
+                    break;
+            }
+        }
+
+        public override void Dispose()
+        {
+            (DbTransaction as IDbTransaction)?.Dispose();
+        }
+    }
+
+    public static class CapTransactionExtensions
+    {
+        public static ICapTransaction Begin(this ICapTransaction transaction,
+            IDbTransaction dbTransaction, bool autoCommit = false)
+        {
+
+            transaction.DbTransaction = dbTransaction;
+            transaction.AutoCommit = autoCommit;
+
+            return transaction;
+        }
+
+        public static ICapTransaction Begin(this ICapTransaction transaction,
+            IDbContextTransaction dbTransaction, bool autoCommit = false)
+        {
+
+            transaction.DbTransaction = dbTransaction;
+            transaction.AutoCommit = autoCommit;
+
+            return transaction;
+        }
+    }
+
+}