added enums.

Enum/PlanPriority.cs

@@ -0,0 +1,9 @@
+namespace CarCareTracker.Enum
+{
+    public enum PlanPriority
+    {
+        Critical = 0,
+        Normal = 1,
+        Low = 2
+    }
+}

Enum/PlanProgress.cs

@@ -0,0 +1,10 @@
+namespace CarCareTracker.Enum
+{
+    public enum PlanProgress
+    {
+        Backlog = 0,
+        InProgress = 1,
+        Testing = 2,
+        Done = 3
+    }
+}