Translate Chinese to English for readme file

Translate Chinese  to English for readme file

README.md

 # CAP
-
-[![Travis](https://travis-ci.org/dotnetcore/CAP.svg?branch=master)](https://travis-ci.org/dotnetcore/CAP)
+[![Travis branch](https://img.shields.io/travis/dotnetcore/CAP/master.svg?label=travis-ci)](https://travis-ci.org/dotnetcore/CAP)
 [![AppVeyor](https://ci.appveyor.com/api/projects/status/4mpe0tbu7n126vyw?svg=true)](https://ci.appveyor.com/project/yuleyule66/cap)
 [![GitHub license](https://img.shields.io/badge/license-MIT-blue.svg)](https://raw.githubusercontent.com/dotnetcore/CAP/master/LICENSE.txt)
 
-A .net core middleware of eventually consistent in distributed architectures, now developing...
+CAP is a library to achieve eventually consistent in distributed architectures system like SOA,MicroService. It is lightweight,easy to use and efficiently
+
+## OverView
+
+CAP is a library that used in an ASP.NET Core project,Of Course you can ues it in ASP.NET Core with .NET Framework 
+
+You can think of CAP as an EventBus because it has all the features of EventBus, and CAP provides a easier way to handle the publishing and subscribing in EventBus.
+
+CAP has the function of message persistence, and it guarantees the reliability of the message when your service is restarted or down. CAP provides a Microsoft Pro-based Producer Service service that integrates seamlessly with your business services and supports strong consistency transactions.
+
+This is a diagram of the CAP work in the ASP.NET Core MicroService architecture:
+
+![](http://images2015.cnblogs.com/blog/250417/201706/250417-20170630143600289-1065294295.png)
+
+> The solid line in the figure represents the user code, and the dotted line represents the internal implementation of the CAP.
+
+## Getting Started
+
+### NuGet (Coming soon)
+
+你可以运行以下下命令在你的项目中安装 CAP。
+
+如果你的消息队列使用的是 Kafka 的话，你可以：
+
+```
+PM> Install-Package DotNetCore.CAP.Kafka
+```
+
+如果你的消息队列使用的是 RabbitMQ 的话，你可以：
+
+```
+PM> Install-Package DotNetCore.CAP.RabbitMQ
+```
+
+CAP 默认提供了 Entity Framwork 作为数据库存储：
+
+```
+PM> Install-Package DotNetCore.CAP.EntityFrameworkCore
+```
+
+### Configuration
+
+首先配置CAP到 Startup.cs 文件中，如下：
+
+```cs
+public void ConfigureServices(IServiceCollection services)
+{
+	......
+
+    services.AddDbContext<AppDbContext>();
+
+    services.AddCap()
+            .AddEntityFrameworkStores<AppDbContext>()
+            .AddKafka(x => x.Servers = "localhost:9453");
+}
+
+public void Configure(IApplicationBuilder app)
+{
+	.....
+
+    app.UseCap();
+}
+
+```
+
+### 发布
+
+在 Controller 中注入 `ICapProducerService` 然后使用 `ICapProducerService` 进行消息发送
+
+```cs
+public class PublishController : Controller
+{
+	private readonly ICapProducerService _producer;
+
+	public PublishController(ICapProducerService producer)
+	{
+		_producer = producer;
+	}
+
+
+	[Route("~/checkAccount")]
+	public async Task<IActionResult> PublishMessage()
+	{
+		//指定发送的消息头和内容
+		await _producer.SendAsync("xxx.services.account.check", new Person { Name = "Foo", Age = 11 });
+
+		return Ok();
+	}
+}
+
+```
+
+### 订阅
+
+**Action Method**
+
+在Action上添加 Attribute 来订阅相关消息。
+
+如果你使用的是 Kafak 则使用 `[KafkaTopic()]`, 如果是 RabbitMQ 则使用 `[RabbitMQTopic()]`
+
+```cs
+public class PublishController : Controller
+{
+	private readonly ICapProducerService _producer;
+
+	public PublishController(ICapProducerService producer)
+	{
+		_producer = producer;
+	}
+
+
+	[NoAction]
+	[KafkaTopic("xxx.services.account.check")]
+	public async Task CheckReceivedMessage(Person person)
+	{
+		Console.WriteLine(person.Name);
+		Console.WriteLine(person.Age);     
+		return Task.CompletedTask;
+	}
+}
+
+```
+
+**Service Method**
+
+如果你的订阅方法没有位于 Controller 中，则你订阅的类需要继承 `IConsumerService`：
+
+```cs
+
+namespace xxx.Service
+{
+	public interface ISubscriberService
+	{
+		public void CheckReceivedMessage(Person person);
+	}
+
+
+	public class SubscriberService: ISubscriberService, IConsumerService
+	{
+		[KafkaTopic("xxx.services.account.check")]
+		public void CheckReceivedMessage(Person person)
+		{
+			
+		}
+	}
+}
+
+```
+
+then inject your  `ISubscriberService`  class in Startup.cs 
+
+```cs
+public void ConfigureServices(IServiceCollection services)
+{
+	services.AddTransient<ISubscriberService,SubscriberService>();
+}
+```
 
-### Contribute
+## Contribute
 
 One of the easiest ways to contribute is to participate in discussions and discuss issues. You can also contribute by submitting pull requests with code changes.