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_Create.sql

@@ -0,0 +1,43 @@
+CREATE PROCEDURE [dbo].[User_Create]
+    @Id UNIQUEIDENTIFIER,
+    @Name NVARCHAR(50),
+    @Email NVARCHAR(50),
+    @MasterPassword NVARCHAR(300),
+    @MasterPasswordHint NVARCHAR(50),
+    @Culture NVARCHAR(10),
+    @SecurityStamp NVARCHAR(50),
+    @TwoFactorEnabled BIT,
+    @TwoFactorProvider TINYINT,
+    @AuthenticatorKey NVARCHAR(50),
+    @CreationDate DATETIME2(7)
+AS
+BEGIN
+    INSERT INTO [dbo].[User]
+    (
+        [Id],
+        [Name],
+        [Email],
+        [MasterPassword],
+        [MasterPasswordHint],
+        [Culture],
+        [SecurityStamp],
+        [TwoFactorEnabled],
+        [TwoFactorProvider],
+        [AuthenticatorKey],
+        [CreationDate]
+    )
+    VALUES
+    (
+        @Id,
+        @Name,
+        @Email,
+        @MasterPassword,
+        @MasterPasswordHint,
+        @Culture,
+        @SecurityStamp,
+        @TwoFactorEnabled,
+        @TwoFactorProvider,
+        @AuthenticatorKey,
+        @CreationDate
+    )
+END