GetAllContentsByRef doesn't properly handle trailing slash

[jepetty]

Hi! We're using Octokit.NET in our service, and we found a bug where it doesn't look like it's properly handling trailing slashes in GetAllContentsByRef. The repo, commitId, and tree we use for testing is vs-threading.

In our first test call, we call:

client.Repository.Content.GetAllContentsByRef("Microsoft", "vs-threading", "src/IsolatedTestHost", "1e187c0a93afb43f08cc36517b44b653a8934b79")

and we get the expected response of 4 files in the tree. When we call it again though but with a trailing slash on our path (like so):

client.Repository.Content.GetAllContentsByRef("Microsoft", "vs-threading", "src/IsolatedTestHost/", "1e187c0a93afb43f08cc36517b44b653a8934b79")

we get an additional file App.Config which does not exist at the commit specified, but does at a later commit.

Looks like somehow the response is coming from the default branch?