Send azure upload (#1334)

* Add direct upload api endpoints

* Create azure upload service

* Update max file size

* Update send file upload test

* Move internationalization string to correct document

* Allow for one shot blob uploads

* Remove unused helper

* Use FileUploadService

Fallback to legacy method on old server implementations.

src/Core/Services/BitwardenFileUploadService.cs

@@ -0,0 +1,26 @@
+using System;
+using System.Net.Http;
+using System.Threading.Tasks;
+
+namespace Bit.Core.Services
+{
+    public class BitwardenFileUploadService
+    {
+        public BitwardenFileUploadService(ApiService apiService)
+        {
+            _apiService = apiService;
+        }
+
+        private readonly ApiService _apiService;
+
+        public async Task Upload(string encryptedFileName, byte[] encryptedFileData, Func<MultipartFormDataContent, Task> apiCall)
+        {
+            var fd = new MultipartFormDataContent($"--BWMobileFormBoundary{DateTime.UtcNow.Ticks}")
+            {
+                { new ByteArrayContent(encryptedFileData), "data", encryptedFileName }
+            };
+
+            await apiCall(fd);
+        }
+    }
+}