Add some comments

Author: jcansdale

src/GitHub.Exports/Services/IGitHubServiceProvider.cs

@@ -31,8 +31,18 @@ Ret GetService<T, Ret>() where T : class
         /// or if it's null, the service will be removed without checking for ownership</param>
         void RemoveService(Type t, object owner);
 
+        /// <summary>
+        /// Gets a Visual Studio service asynchronously.
+        /// </summary>
+        /// <typeparam name="T">The type of the service.</typeparam>
         Task<T> GetServiceAsync<T>() where T : class;
 
+        /// <summary>
+        /// Gets a Visual Studio service asynchronously.
+        /// </summary>
+        /// <typeparam name="T">The type of the service.</typeparam>
+        /// <typeparam name="Ret">The type of the service instance to return.</typeparam>
+        /// <returns></returns>
         [SuppressMessage("Microsoft.Design", "CA1004:GenericMethodsShouldProvideTypeParameter")]
         Task<Ret> GetServiceAsync<T, Ret>() where T : class where Ret : class;
     }

src/GitHub.TeamFoundation.14/Services/VSGitExt.cs

@@ -17,7 +17,7 @@ namespace GitHub.VisualStudio.Base
     /// </summary>
     /// <remarks>
     /// Initialization for this service will be done asynchronously and the <see cref="IGitExt" /> service will be
-    /// retrieved on the Main thread. This means the service can be constructed and subscribed to on a background thread.
+    /// retrieved using <see cref="GetServiceAsync" />. This means the service can be constructed and subscribed to from a background thread.
     /// </remarks>
     public class VSGitExt : IVSGitExt
     {

src/GitHub.VisualStudio/GitHubPackage.cs

@@ -300,6 +300,7 @@ async Task<object> CreateService(IAsyncServiceContainer container, CancellationT
 
         IVSGitExt CreateVSGitExt(string dteVersion, IGitHubServiceProvider sp)
         {
+            // DTE.Version always ends with ".0" even for later minor versions.
             switch (dteVersion)
             {
                 case "14.0":