Adds explicit alignment information for alloca instructions in general, there's a few cases that still needs to be looked at but this should catch the majority. Fixes ticket #293 .

interface IN
{
    void func();
}
abstract class AC
{
    abstract void func();
    long ll;
}
class C : AC
{
    void func()
    {
    }
}

void main()
{
    scope c = new C;
}