Feature #33: Enhanced Device Importing

Dynamic device importing. better input parsing and 5 additional import
fields.

Disco.Models/Services/Devices/Importing/IDeviceImportField.cs

@@ -0,0 +1,21 @@
+using System;
+using System.Collections.Generic;
+using System.Data;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Disco.Models.Services.Devices.Importing
+{
+    public interface IDeviceImportField
+    {
+        DeviceImportFieldTypes FieldType { get; }
+        EntityState? FieldAction { get; }
+        
+        string ErrorMessage { get; }
+
+        object RawParsedValue { get; }
+        string FriendlyValue { get; }
+        string FriendlyPreviousValue { get; }
+    }
+}