Fix VarDecls for tuples. Closes #99. I've implemented it this way since it doesn't require any changes in the frontend. However, I think having TypeTuple expressed as LLVM struct types would make much more sense and open the door to tuple lvalues.

module alignment;

align(1) struct S
{
    ubyte b;
    int i;
    ubyte[2] b2;
    long l;
    real r;
}

void main()
{
    byte b;
    short s;
    int i;
    long l;
    float f;
    double d;
    real r;
}