Add public proxy APIs

Author: bording

LibGit2Sharp/FetchOptionsBase.cs

@@ -48,5 +48,7 @@ internal FetchOptionsBase()
         /// Completed operating on the current repository.
         /// </summary>
         public RepositoryOperationCompleted RepositoryOperationCompleted { get; set; }
+
+        public ProxyOptions ProxyOptions { get; set; }
     }
 }

LibGit2Sharp/ProxyOptions.cs

@@ -0,0 +1,15 @@
+using LibGit2Sharp.Handlers;
+
+namespace LibGit2Sharp
+{
+    public class ProxyOptions
+    {
+        public ProxyType ProxyType { get; set; }
+
+        public string Url { get; set; }
+
+        public CredentialsHandler CredentialsProvider { get; set; }
+
+        public CertificateCheckHandler CertificateCheck { get; set; }
+    }
+}

LibGit2Sharp/ProxyType.cs

@@ -0,0 +1,9 @@
+namespace LibGit2Sharp
+{
+    public enum ProxyType
+    {
+        None,
+        Auto,
+        Specified
+    }
+}