Allow blank lines before doc’ed declarations

Previously, we would compress

    "Some thing"
    Anything thing;

    "Another thing"
    Anything thingy;

into

    "Some thing"
    Anything thing;
    "Another thing"
    Anything thingy;

Because the string literal didn’t allow blank lines above it.
Fix SequencedType space bug

Anything+things → Anything+ things