Implemented tax collection for subscriptions (#1017)

* Implemented tax collection for subscriptions

* Cleanup for Sales Tax

* Cleanup for Sales Tax

* Changes a constraint to an index for checking purposes

* Added and implemented a ReadById method for TaxRate

* Code review fixes for Tax Rate implementation

* Code review fixes for Tax Rate implementation

* Made the SalesTax migration script rerunnable

util/Migrator/DbScripts/2020-11-16_00_SalesTax.sql

@@ -0,0 +1,149 @@
+IF OBJECT_ID('[dbo].[Policy]') IS NULL
+BEGIN
+    CREATE TABLE [dbo].[TaxRate] (
+        [Id]                VARCHAR(40)         NOT NULL,
+        [Country]           VARCHAR(50)         NOT NULL,
+        [State]             VARCHAR(2)          NULL,
+        [PostalCode]        VARCHAR(10)         NOT NULL,
+        [Rate]              DECIMAL(5,2)        NOT NULL,
+        [Active]            BIT                 NOT NULL,
+        CONSTRAINT [PK_TaxRate] PRIMARY KEY CLUSTERED ([Id] ASC)
+    );
+
+    CREATE UNIQUE INDEX [IX_TaxRate_Country_PostalCode_Active_Uniqueness]
+    ON [dbo].[TaxRate](Country, PostalCode)
+    WHERE Active = 1;
+END
+GO
+
+IF OBJECT_ID('[dbo].[TaxRate_ReadById]') IS NOT NULL
+BEGIN
+    DROP PROCEDURE [dbo].[TaxRate_ReadById]
+END
+GO
+
+CREATE PROCEDURE [dbo].[TaxRate_ReadById]
+    @Id VARCHAR(40)
+AS
+BEGIN
+    SET NOCOUNT ON 
+
+    SELECT * FROM [dbo].[TaxRate]
+    WHERE Id = @Id
+END
+GO
+
+IF OBJECT_ID('[dbo].[TaxRate_Search]') IS NOT NULL
+BEGIN
+    DROP PROCEDURE [dbo].[TaxRate_Search]
+END
+GO
+
+CREATE PROCEDURE [dbo].[TaxRate_Search]
+    @Skip INT = 0,
+    @Count INT = 25
+AS
+BEGIN
+    SET NOCOUNT ON 
+    
+    SELECT * FROM [dbo].[TaxRate]
+    WHERE Active = 1
+    ORDER BY Country, PostalCode DESC
+    OFFSET @Skip ROWS
+    FETCH NEXT @Count ROWS ONLY
+END
+GO
+
+IF OBJECT_ID('[dbo].[TaxRate_ReadAllActive]') IS NOT NULL
+BEGIN
+    DROP PROCEDURE [dbo].[TaxRate_ReadAllActive]
+END
+GO
+
+CREATE PROCEDURE [dbo].[TaxRate_ReadAllActive]
+AS
+BEGIN
+    SET NOCOUNT ON 
+    
+    SELECT * FROM [dbo].[TaxRate]
+    WHERE Active = 1
+END
+GO
+
+IF OBJECT_ID('[dbo].[TaxRate_ReadByLocation]') IS NOT NULL
+BEGIN
+    DROP PROCEDURE [dbo].[TaxRate_ReadByLocation]
+END
+GO
+
+CREATE PROCEDURE [dbo].[TaxRate_ReadByLocation]
+    @Country VARCHAR(50),
+    @PostalCode VARCHAR(10)
+AS
+BEGIN
+    SET NOCOUNT ON 
+    
+    SELECT * FROM [dbo].[TaxRate]
+    WHERE Active = 1
+        AND [Country] = @Country
+        AND [PostalCode] = @PostalCode
+END
+GO
+
+IF OBJECT_ID('[dbo].[TaxRate_Create]') IS NOT NULL
+BEGIN
+    DROP PROCEDURE [dbo].[TaxRate_Create]
+END
+GO
+
+CREATE PROCEDURE [dbo].[TaxRate_Create]
+    @Id VARCHAR(40),
+    @Country VARCHAR(50),
+    @State VARCHAR(2),
+    @PostalCode VARCHAR(10),
+    @Rate DECIMAL(5,2),
+    @Active BIT
+AS
+BEGIN
+    SET NOCOUNT ON
+
+    INSERT INTO [dbo].[TaxRate]
+    (
+        [Id],
+        [Country],
+        [State],
+        [PostalCode],
+        [Rate],
+        [Active]
+    )
+    VALUES
+    (
+        @Id,
+        @Country,
+        @State,
+        @PostalCode,
+        @Rate,
+        1
+    )
+END
+GO
+
+IF OBJECT_ID('[dbo].[TaxRate_Archive]') IS NOT NULL
+BEGIN
+    DROP PROCEDURE [dbo].[TaxRate_Archive]
+END
+GO
+
+CREATE PROCEDURE [dbo].[TaxRate_Archive]
+    @Id VARCHAR(40)
+AS
+BEGIN
+    SET NOCOUNT ON
+
+    UPDATE
+        [dbo].[TaxRate]
+    SET
+        [Active] = 0
+    WHERE
+        [Id] = @Id
+END