NuSpec for automatic imported MSBuild target file which imports another one installed at the same time by NuGet

MSBuildTasks.ImportTasks.nuspec

<?xml version="1.0"?>
<package>
  <metadata>
    <id>MSBuildTasks.ImportTasks</id>
    <version>0.1.0.0</version>
    <title>MSBuildTasks.ImportTasks</title>
    <authors>tmori3y2</authors>
    <owners>tmori3y2</owners>
    <projectUrl>http://tmori3y2.hatenablog.com/</projectUrl>
    <requireLicenseAcceptance>false</requireLicenseAcceptance>
    <developmentDependency>true</developmentDependency>
    <description>MSBuild Task to Import Tasks from build folder.</description>
    <releaseNotes>The first release.</releaseNotes>
    <copyright>Copyright (C) 2016 tmori3y2</copyright>
    <tags>MSBuild</tags>
  </metadata>
  <files>
    <file src="nupkg\build\*.*" target="build" />
    <file src="nupkg\content\build\*.*" target="content\build" />
    <file src="bin\**\*.*" exclude="**\*.*" />
  </files>
</package>

https://github.com/tmori3y2/BlogSamples/blob/Article_20160321/NuGetPackages/MSBuildTasks/MSBuildTasks.ImportTasks/MSBuildTasks.ImportTasks.nuspec