feature: supports to de-initialize a submodule (#1272)

Signed-off-by: leo <longshuang@msn.cn>

src/ViewModels/DeinitSubmodule.cs

@@ -0,0 +1,45 @@
+using System.Threading.Tasks;
+
+namespace SourceGit.ViewModels
+{
+    public class DeinitSubmodule : Popup
+    {
+        public string Submodule
+        {
+            get;
+            private set;
+        }
+
+        public bool Force
+        {
+            get;
+            set;
+        }
+
+        public DeinitSubmodule(Repository repo, string submodule)
+        {
+            _repo = repo;
+            Submodule = submodule;
+            Force = false;
+        }
+
+        public override Task<bool> Sure()
+        {
+            _repo.SetWatcherEnabled(false);
+            ProgressDescription = "De-initialize Submodule";
+
+            var log = _repo.CreateLog("De-initialize Submodule");
+            Use(log);
+
+            return Task.Run(() =>
+            {
+                var succ = new Commands.Submodule(_repo.FullPath).Use(log).Deinit(Submodule, false);
+                log.Complete();
+                CallUIThread(() => _repo.SetWatcherEnabled(true));
+                return succ;
+            });
+        }
+
+        private Repository _repo;
+    }
+}