[svn r86] Changed the way arguments are given storage. It is now detected if they will need it during semantic passes. Initial support for debug information. Very limited, but MUCH better than nothing :)

module bug1;
struct Foo { Foo opSub(ref Foo b) { return Foo(); } }
struct Bar { Foo whee; }
void test(ref Bar moo) { Foo nngh; auto plonk = nngh - moo.whee; }
void main() { Bar bar; test(bar); }