MCPU Processor.b ; Set cpu routines allowed to use. 0..3=000..030, or >3=040+. CAREFUL!!

Sets the general CPU specification that the user has available. This will enable
Mildred to use specially optimised routines where possible to provide better
performance on particular processors. You should pass the blitz `Processor'
instruction or the new MProcessor command as the parameter in which values of
0..3 represent that the user has a 68030 or lower, and a 4 or 6 represents
that they have a 68040 or higher. Be sure that the user does have the
processor you are specifying as, unlike Mc2pCPUmode (which is seperate
entirely), it is possible to crash the computer if you attempt to use
routines for a cpu that is not capable of certain instructions (such as 040+
routines). This problem is usually avoided by simply using the blitz
`Processor' instruction or MProcessor. MCPU should be used near to the start
of your program before performing any operations that use chunky Shapes and
chunky Bitmaps, although since v1.36 it will be automatically set internally
according to what cpu is available at runtime. If you do not wish to override
this you can forget about having to set a CPU mode.