Visual changes on device create (#480)

* Visual changes on general tab

* Visual changes on LoRa tab + Fix missing UseOTAA property

* Fixed missing image when selecting LoRa Model

* Added unit tests

* Fix alignment and useless "using"

src/AzureIoTHub.Portal.Server.Tests.Unit/Validators/DeviceDetailValidatorTests.cs

@@ -0,0 +1,77 @@
+// Copyright (c) CGI France. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+namespace AzureIoTHub.Portal.Server.Tests.Unit.Validators
+{
+    using System;
+    using AzureIoTHub.Portal.Client.Validators;
+    using AzureIoTHub.Portal.Models.v10;
+    using NUnit.Framework;
+
+    [TestFixture]
+    internal class DeviceDetailsValidatorTests
+    {
+        [Test]
+        public void ValidateValidDevice()
+        {
+
+            // Arrange
+            var standardValidator = new DeviceDetailsValidator();
+            var device = new DeviceDetails()
+            {
+                DeviceName = Guid.NewGuid().ToString(),
+                ModelId = Guid.NewGuid().ToString(),
+                DeviceID = Guid.NewGuid().ToString(),
+            };
+
+            // Act
+            var standardValidation = standardValidator.Validate(device);
+
+            // Assert
+            Assert.IsTrue(standardValidation.IsValid);
+            Assert.AreEqual(0, standardValidation.Errors.Count);
+        }
+
+        [TestCase("DeviceName", "", "ModelIdValue", "DeviceIDValue")]
+        [TestCase("ModelId", "DeviceNameValue", "", "DeviceIDValue")]
+        [TestCase("DeviceID", "DeviceNameValue", "ModelIdValue", "")]
+        public void ValidateMissingFieldShouldReturnError(
+            string testedValue,
+            string DeviceNameValue,
+            string ModelIdValue,
+            string DeviceIDValue)
+        {
+            // Arrange
+            var standardValidator = new DeviceDetailsValidator();
+            var device = new DeviceDetails()
+            {
+                DeviceName = DeviceNameValue,
+                ModelId =ModelIdValue,
+                DeviceID = DeviceIDValue,
+            };
+
+            // Act
+            var standardValidation = standardValidator.Validate(device);
+
+            // Assert
+            Assert.IsFalse(standardValidation.IsValid);
+            Assert.AreEqual(1, standardValidation.Errors.Count);
+            Assert.AreEqual(standardValidation.Errors[0].ErrorMessage, $"{testedValue} is required.");
+        }
+
+        [Test]
+        public void ValidateAllFieldsEmptyShouldReturnError()
+        {
+            // Arrange
+            var standardValidator = new DeviceDetailsValidator();
+            var device = new DeviceDetails();
+
+            // Act
+            var standardValidation = standardValidator.Validate(device);
+
+            // Assert
+            Assert.IsFalse(standardValidation.IsValid);
+            Assert.AreEqual(3, standardValidation.Errors.Count);
+        }
+    }
+}