Select multiple pull down issue

[jwdebelius]

When a multiple selection question is pulled down (i.e allergic_to_), a column describing "unspecified" is pulled down as a boolean. This boolean of "unspecified" should be propagated across the samples, making the possible values for other columns "Yes", "No" and "Unspecified" and "not applicable" (blanks).

Additionally, the pulldown includes an empty column that represents the block question, and carries not additional data.