Add ReSharper external annotations to NuGet file.

Author: drewnoakes

MetadataExtractor/MetadataExtractor.nuspec

@@ -37,9 +37,14 @@
   <files>
     <file src="bin\Release\net35\MetadataExtractor.dll" target="lib\net35\" />
     <file src="bin\Release\net35\MetadataExtractor.xml" target="lib\net35\" />
+    <file src="bin\Release\net35\MetadataExtractor.ExternalAnnotations.xml" target="lib\net35\" />
+
     <file src="bin\Release\net45\MetadataExtractor.dll" target="lib\net45\" />
     <file src="bin\Release\net45\MetadataExtractor.xml" target="lib\net45\" />
+    <file src="bin\Release\net45\MetadataExtractor.ExternalAnnotations.xml" target="lib\net45\" />
+
     <file src="bin\Release\Portable\MetadataExtractor.Portable.dll" target="lib\portable-net45+sl50+netcore45+wpa81+wp8\" />
     <file src="bin\Release\Portable\MetadataExtractor.Portable.xml" target="lib\portable-net45+sl50+netcore45+wpa81+wp8\" />
+    <file src="bin\Release\Portable\MetadataExtractor.Portable.ExternalAnnotations.xml" target="lib\portable-net45+sl50+netcore45+wpa81+wp8\" />
   </files>
 </package>