Add Volo.Abp.Specifications package reference to the Volo.Abp.Ddd.Domain package.

docs/en/Specifications.md

@@ -2,9 +2,13 @@
 
 Specification Pattern is used to define **named, reusable, combinable and testable filters** for entities and other business objects.
 
+> A Specification is a part of the Domain Layer.
+
 ## Installation
 
-If you haven't installed yet, install the [Volo.Abp.Specifications](https://abp.io/package-detail/Volo.Abp.Specifications) package to your project. You can use the [ABP CLI](CLI.md) *add-package* command in a command line terminal when the current folder is the root folder of your project (`.csproj`):
+> This package is **already installed** when you use the startup templates. So, most of the times you don't need to manually install it.
+
+Install the [Volo.Abp.Specifications](https://abp.io/package-detail/Volo.Abp.Specifications) package to your project. You can use the [ABP CLI](CLI.md) *add-package* command in a command line terminal when the current folder is the root folder of your project (`.csproj`):
 
 ````bash
 abp add-package Volo.Abp.Specifications

framework/src/Volo.Abp.Ddd.Domain/Volo.Abp.Ddd.Domain.csproj

@@ -22,6 +22,7 @@
     <ProjectReference Include="..\Volo.Abp.Guids\Volo.Abp.Guids.csproj" />
     <ProjectReference Include="..\Volo.Abp.MultiTenancy\Volo.Abp.MultiTenancy.csproj" />
     <ProjectReference Include="..\Volo.Abp.ObjectMapping\Volo.Abp.ObjectMapping.csproj" />
+    <ProjectReference Include="..\Volo.Abp.Specifications\Volo.Abp.Specifications.csproj" />
     <ProjectReference Include="..\Volo.Abp.Threading\Volo.Abp.Threading.csproj" />
     <ProjectReference Include="..\Volo.Abp.Timing\Volo.Abp.Timing.csproj" />
     <ProjectReference Include="..\Volo.Abp.Uow\Volo.Abp.Uow.csproj" />

framework/src/Volo.Abp.Ddd.Domain/Volo/Abp/Domain/AbpDddDomainModule.cs

@@ -6,6 +6,7 @@ using Volo.Abp.Guids;
 using Volo.Abp.Modularity;
 using Volo.Abp.MultiTenancy;
 using Volo.Abp.ObjectMapping;
+using Volo.Abp.Specifications;
 using Volo.Abp.Threading;
 using Volo.Abp.Timing;
 using Volo.Abp.Uow;
@@ -22,7 +23,8 @@ namespace Volo.Abp.Domain
         typeof(AbpTimingModule),
         typeof(AbpUnitOfWorkModule),
         typeof(AbpObjectMappingModule),
-        typeof(AbpExceptionHandlingModule)
+        typeof(AbpExceptionHandlingModule),
+        typeof(AbpSpecificationsModule)
         )]
     public class AbpDddDomainModule : AbpModule
     {