Update //third_party/protobuf to version 3.

third_party/protobuf/csharp/src/Google.Protobuf/Google.Protobuf.nuspec

Index: third_party/protobuf/csharp/src/Google.Protobuf/Google.Protobuf.nuspec
diff --git a/third_party/protobuf/csharp/src/Google.Protobuf/Google.Protobuf.nuspec b/third_party/protobuf/csharp/src/Google.Protobuf/Google.Protobuf.nuspec
new file mode 100644
index 0000000000000000000000000000000000000000..2f691e3c3d51dd626eda1a21b26dd917f799504f
--- /dev/null
+++ b/third_party/protobuf/csharp/src/Google.Protobuf/Google.Protobuf.nuspec
@@ -0,0 +1,56 @@
+<?xml version="1.0" encoding="utf-8"?>
+<package>
+  <metadata>
+    <id>Google.Protobuf</id>
+    <title>Google Protocol Buffers C#</title>
+    <summary>C# runtime library for Protocol Buffers - Google's data interchange format.</summary>
+    <description>See project site for more info.</description>
+    <version>3.0.0-beta2</version>
+    <authors>Google Inc.</authors>
+    <owners>protobuf-packages</owners>
+    <licenseUrl>https://github.com/google/protobuf/blob/master/LICENSE</licenseUrl>
+    <projectUrl>https://github.com/google/protobuf</projectUrl>
+    <requireLicenseAcceptance>false</requireLicenseAcceptance>
+    <releaseNotes>C# proto3 support</releaseNotes>
+    <copyright>Copyright 2015, Google Inc.</copyright>
+    <tags>Protocol Buffers Binary Serialization Format Google proto proto3</tags>
+    <dependencies>
+      <group targetFramework="dotnet">
+        <dependency id="System.Collections" version="4.0.0" />
+        <dependency id="System.Diagnostics.Debug" version="4.0.0" />
+        <dependency id="System.Globalization" version="4.0.0" />
+        <dependency id="System.IO" version="4.0.0" />
+        <dependency id="System.Linq" version="4.0.0" />
+        <dependency id="System.Linq.Expressions" version="4.0.0" />
+        <dependency id="System.ObjectModel" version="4.0.0" />
+        <dependency id="System.Reflection" version="4.0.0" />
+        <dependency id="System.Runtime" version="4.0.0" />
+        <dependency id="System.Runtime.Extensions" version="4.0.0" />
+        <dependency id="System.Text.Encoding" version="4.0.0" />
+        <dependency id="System.Text.RegularExpressions" version="4.0.0" />
+      </group>
+    </dependencies>
+  </metadata>
+  <files>
+    <file src="bin/ReleaseSigned/Google.Protobuf.dll" target="lib/portable-net45+netcore45+wpa81+wp8" />
+    <file src="bin/ReleaseSigned/Google.Protobuf.pdb" target="lib/portable-net45+netcore45+wpa81+wp8" />
+    <file src="bin/ReleaseSigned/Google.Protobuf.xml" target="lib/portable-net45+netcore45+wpa81+wp8" />
+    <file src="bin/ReleaseSigned/Google.Protobuf.dll" target="lib/dotnet" />
+    <file src="bin/ReleaseSigned/Google.Protobuf.pdb" target="lib/dotnet" />
+    <file src="bin/ReleaseSigned/Google.Protobuf.xml" target="lib/dotnet" />
+    <file src="**\*.cs" target="src" />
+    <file src="..\..\..\cmake\Release\protoc.exe" target="tools" />
+    <file src="..\..\..\src\google\protobuf\any.proto" target="tools\google\protobuf" />
+    <file src="..\..\..\src\google\protobuf\api.proto" target="tools\google\protobuf" />
+    <file src="..\..\..\src\google\protobuf\descriptor.proto" target="tools\google\protobuf" />
+    <file src="..\..\..\src\google\protobuf\duration.proto" target="tools\google\protobuf" />
+    <file src="..\..\..\src\google\protobuf\empty.proto" target="tools\google\protobuf" />
+    <file src="..\..\..\src\google\protobuf\field_mask.proto" target="tools\google\protobuf" />
+    <file src="..\..\..\src\google\protobuf\source_context.proto" target="tools\google\protobuf" />
+    <file src="..\..\..\src\google\protobuf\struct.proto" target="tools\google\protobuf" />
+    <file src="..\..\..\src\google\protobuf\timestamp.proto" target="tools\google\protobuf" />
+    <file src="..\..\..\src\google\protobuf\any.proto" target="tools\google\protobuf" />
+    <file src="..\..\..\src\google\protobuf\type.proto" target="tools\google\protobuf" />
+    <file src="..\..\..\src\google\protobuf\wrappers.proto" target="tools\google\protobuf" />
+  </files>
+</package>