Added Sql project with database schema. Added SqlServer repositories for Site, Folder, and User (Cipher still TODO). Switched DI in Startup to SqlServer repos.

src/Sql/dbo/Stored Procedures/User_ReadById.sql

@@ -0,0 +1,11 @@
+CREATE PROCEDURE [dbo].[User_ReadById]
+    @Id UNIQUEIDENTIFIER
+AS
+BEGIN
+    SELECT
+        *
+    FROM
+        [dbo].[UserView]
+    WHERE
+        [Id] = @Id
+END