MJ8 additions

[shorowit]

• Blower fan heat: Add an optional blower fan heat Btuh input. Default to 1707. Need to handle special case where 0 is entered (i.e., the user wants a design load w/o blower fan heat because they will be selecting equipment using gross capacity, not net capacity), in which case we'll need to add the 1707 to the design load when calculating the autosized equipment capacity. Also document that capacities are net capacities.
• Hot water piping: Add an optional Btuh input.
• Humidification: Add an optional Btuh input.
• Partitions: Change garage to be not exposed, consistent with our temperature/modeling assumptions (Add an optional input for whether the garage is often open?)
• Skylights: Allow skylights with light shafts or tubular skylights #1659. Add curb area/Rvalue and shaft area/Rvalue inputs. Model shaft as knee wall in energy model. Document area adjustment for dome.
• Infiltration: Allow qualitative infiltration inputs (average, tight, etc.) #1652
• Shading: Add optional ISC/ESC inputs for Manual J.
• Investigate duct load multipliers for ventilation that produces a space load @yzhou601
• Incorporate duct leakage imbalance?