add interface of producer.

src/Cap.Consistency/Cap.Consistency.csproj

 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netstandard1.6</TargetFramework>
     <PackageId>Cap.Consistency</PackageId>
+    <TargetFramework>netstandard1.6</TargetFramework>
     <NetStandardImplicitPackageVersion>1.6.1</NetStandardImplicitPackageVersion>
     <PackageTargetFallback>$(PackageTargetFallback);dnxcore50</PackageTargetFallback>
   </PropertyGroup>

src/Cap.Consistency/Producer/IProducerClient.cs

+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Cap.Consistency.Producer
+{
+    public interface IProducerClient
+    {
+
+
+
+    }
+}