Implement MxAtomId and reference counter (stl set) (#109)

* Implement MxAtomId and reference counter (stl set)
* Partial success in hiding 4786 warning spam.
* Build out most of MxOmni::Destroy since it also touches the set

* Add some size asserts

LEGO1/mxatomidcounter.h

@@ -0,0 +1,49 @@
+#ifndef MXATOMIDCOUNTER_H
+#define MXATOMIDCOUNTER_H
+
+#include "mxstring.h"
+#include "compat.h" // STL
+
+// Counts the number of existing MxAtomId objects based
+// on the matching char* string. A <map> seems fit for purpose here:
+// We have an MxString as a key and MxU16 as the value.
+// And yet a <set> is the best match. The malloc in MxOmni::Create
+// for the _Nil node asks for more bytes than a regular node if a <map>
+// is used, but all nodes are 20 bytes wide with a <set>.
+// Also: the increment/decrement methods suggest a custom type was used
+// for the combined key_value_pair, which doesn't seem possible with <map>.
+
+// SIZE: 0x14 (including padding)
+class MxAtomIdCounter
+{
+public:
+  // always inlined
+  MxAtomIdCounter(const char *p_str)
+  {
+    m_key = p_str;
+    m_value = 0;
+  }
+
+  void Inc();
+  void Dec();
+  inline MxString* GetKey() { return &m_key; };
+  inline MxU16 GetValue() { return m_value; };
+
+private:
+  MxString m_key;
+  MxU16 m_value;
+};
+
+struct MxAtomIdCounterCompare
+{
+  // OFFSET: LEGO1 0x100ad120
+  int operator()(MxAtomIdCounter* const & p_val0, MxAtomIdCounter* const & p_val1) const
+  {
+    return strcmp(p_val0->GetKey()->GetData(), p_val1->GetKey()->GetData()) > 0;
+  }
+};
+
+class MxAtomIdCounterSet : public set<MxAtomIdCounter*, MxAtomIdCounterCompare>
+{};
+
+#endif //MXATOMIDCOUNTER_H