* All of the MxVectors share an inheritance chain. MxVector4 inherits
from MxVector3 which inherits from MxVector2.
* They all operate on a shared `float*` data member which points to the
underlying storage.
* There are also MxVector3/4Data classes, which inherit from Vector3/4,
but add concrete storage for the Vector data rather than just an
abstract data pointer.
* The same is true for MxMatrix, with there being an abstract and a
concrete variant of it.
* Also improve reccmp.py register matching algorithm. It previously
could not recognize an effective match when a swap had to take place
between two registers used on the same line. It turns out this happens
a lot in floating point math code so I adjusted the implementation to
break the disassembly lines on spaces rather than just linebreaks
allowing the existing effective match code to handle that case too.
