Expose the underlying reference for ReferenceWrapper

This lets us get to the reference's information without having to ask
the wrapper object for the information.

Author: carlosmn

LibGit2Sharp/Branch.cs

@@ -110,10 +110,10 @@ public virtual bool IsCurrentRepositoryHead
             {
                 if (this is DetachedHead)
                 {
-                    return repo.Head.reference.TargetIdentifier == this.reference.TargetIdentifier;
+                    return repo.Head.Reference.TargetIdentifier == this.Reference.TargetIdentifier;
                 }
 
-                return repo.Head.reference.TargetIdentifier == this.CanonicalName;
+                return repo.Head.Reference.TargetIdentifier == this.CanonicalName;
             }
         }
 

LibGit2Sharp/ReferenceWrapper.cs

@@ -16,7 +16,7 @@ public abstract class ReferenceWrapper<TObject> : IEquatable<ReferenceWrapper<TO
         /// The repository.
         /// </summary>
         protected readonly Repository repo;
-        protected readonly Reference reference;
+        private readonly Reference reference;
         private readonly Lazy<TObject> objectBuilder;
 
         private static readonly LambdaEqualityHelper<ReferenceWrapper<TObject>> equalityHelper =
@@ -61,6 +61,17 @@ public virtual string FriendlyName
             get { return Shorten(); }
         }
 
+        /// <summary>
+        /// The underlying <see cref="Reference"/>
+        /// </summary>
+        public virtual Reference Reference
+        {
+            get
+            {
+                return reference;
+            }
+        }
+
         /// <summary>
         /// Returns the <see cref="CanonicalName"/>, a <see cref="string"/> representation of the current reference.
         /// </summary>