Add support for hierarchyid data type

[drumsta]

CREATE TABLE [HumanResources].[Employee](
    [BusinessEntityID] [int] NOT NULL,
    [NationalIDNumber] [nvarchar](15) NOT NULL,
    [LoginID] [nvarchar](256) NOT NULL,
    [OrganizationNode] [hierarchyid] NULL,
    [OrganizationLevel]  AS ([OrganizationNode].[GetLevel]()),
    [JobTitle] [nvarchar](50) NOT NULL,
    [BirthDate] [date] NOT NULL,
    [MaritalStatus] [nchar](1) NOT NULL,
    [Gender] [nchar](1) NOT NULL,
    [HireDate] [date] NOT NULL,
    [SalariedFlag] [dbo].[Flag] NOT NULL CONSTRAINT [DF_Employee_SalariedFlag]  DEFAULT ((1)),
    [VacationHours] [smallint] NOT NULL CONSTRAINT [DF_Employee_VacationHours]  DEFAULT ((0)),
    [SickLeaveHours] [smallint] NOT NULL CONSTRAINT [DF_Employee_SickLeaveHours]  DEFAULT ((0)),
    [CurrentFlag] [dbo].[Flag] NOT NULL CONSTRAINT [DF_Employee_CurrentFlag]  DEFAULT ((1)),
    [rowguid] [uniqueidentifier] ROWGUIDCOL  NOT NULL CONSTRAINT [DF_Employee_rowguid]  DEFAULT (newid()),
    [ModifiedDate] [datetime] NOT NULL CONSTRAINT [DF_Employee_ModifiedDate]  DEFAULT (getdate()),
 CONSTRAINT [PK_Employee_BusinessEntityID] PRIMARY KEY CLUSTERED 
  ([BusinessEntityID] ASC)
)

SELECT [BusinessEntityID], [OrganizationNode]
FROM HumanResources.Employee