Add libgit2 binaries as Content

This ensures that they're included in the VSIX and are available when
unit testing.

Author: jcansdale

src/GitHub.Exports/GitHub.Exports.csproj

@@ -8,6 +8,14 @@
 
   <Import Project="$(SolutionDir)\src\common\signing.props" />
 
+  <!-- Include libgit2 binaries in VSIX -->
+  <ItemGroup>
+    <None Remove="lib\win32\x86\git2-*" />
+    <Content Include="lib\win32\x86\git2-*">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
+  </ItemGroup>
+
   <ItemGroup>
     <Reference Include="System.ComponentModel.Composition" />
     <Reference Include="System.Net.Http" />