This makes Travis cringe....

```
'LibGit2Sharp.Stash' cannot be easily abstracted in a testing context. Please make sure it either has a public constructor, or an empty protected constructor.
	/home/travis/build/libgit2/libgit2sharp/CI-build.msbuild: error :   at LibGit2Sharp.Tests.MetaFixture.TypesInLibGit2SharpMustBeExtensibleInATestingContext () [0x00000] in <filename unknown>:0 
  at (wrapper managed-to-native) System.Reflection.MonoMethod:InternalInvoke (System.Reflection.MonoMethod,object,object[],System.Exception&)
  at System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x00000] in <filename unknown>:0 
```