Fixing all the memory leaks.

[nemerle]

Despite spending a good chunk of time on switching boomerang over to shared_ptrs, I couldn't solve the memory situation.

Got pretty close with shared_ptr/shared_from_this approach but after putting in 11+ hours into it, it barfed on this little gem:

    this->~PhiAssign(); // Explicitly destroy this, but keep the memory allocated.
    Assign *a = new (this) Assign(type_, lhs_, rhs_); // construct in-place. Note that 'a' == 'this'

So my current thinking is "Copy as much as possible from llvm's approach of single ownership" :

• Prog owns Modules
• Modules own Functions
• Functions own BasicBlocks
• BasicBlocks own Instructions

[ceeac]

Most memory leaks have been fixed in develop now. However, there are still some memory leaks remaining that are difficult to fix - most notably in both parsers. I think it is best to solve these memory leaks after the parser rewrite.