TBD Surfaces Types

We have following types:

1. ->adj Zone when we link to other room, internal surfaces
2. Adiabatic - not heat transfer
3. Exposed - all external surfaces with solar gain
4. Ground - touching ground no solar gain

Const tbdExposed = 1
Member of TBD.SurfaceType
Const tbdGround = 0
Member of TBD.SurfaceType
Const tbdInternal = 2
Member of TBD.SurfaceType
Const tbdLink = 3
Member of TBD.SurfaceType
Const tbdNullLink = 4
Member of TBD.SurfaceType