[Release 1.6.0] Adding documentation for network cmdlets (#2560)

* Added documentation and examples for NSG and NSG.SecurityRule
* More examples for NSG commandlets
* Examples for virtual network and virtual network subnet commands

Author: DeepakRajendranMsft

src/ResourceManager/Network/Commands.Network/Commands.Network.csproj

@@ -502,7 +502,9 @@
       <Link>AzureRM.Network.psd1</Link>
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
-    <None Include="Microsoft.Azure.Commands.Network.dll-Help.psd1" />
+    <None Include="Microsoft.Azure.Commands.Network.dll-Help.psd1">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </None>
     <None Include="Microsoft.Azure.Commands.Network.format.ps1xml">
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
       <SubType>Designer</SubType>