MReMapMode ;Returns value 5 which represents `ReMap' mode in the blit modes (uses current 2-dimensional table)

For use with one of the `BlitMode' commands, such as MBlitMode, the MReMapMode
function can be used in the same way as the default CookieMode, SolidMode,
InvMode and EraseMode. MReMapMode is a new blit mode that will render the source
image to the destination at the same time as performing a remapping of the
colours using a previously created lookup table, ie a Table object. The currently
used table object will be used and it should be a 2 dimensional table of 8-bit
data, ie 256x256 bytes. When MReMapMode is the blit mode of choice, the source
will be blitted to the destination in the manner according to the type of blit
(MBlit, SBlit, etc), but also the source and destination will be combined using
the Table to produce some kind of remapping effect. It depends on what the
Table has been computed for as to what the effect will be, but it is possible to
do things such as semi-transparent merges, brightness changes, add and subtract,
etc. Also you should note that in MReMap mode, the entirity of the Shape's
rectangle will be remapped. It is therefore necessary to build in masking support
to the actual Table, by checking for combinations where the source colour is
colour 0, and using a straight copy of the destination colour for those
combinations. This will cause pixels of 0 in the Shape, for example, to appear to
be transparent, or alternatively you can deliberately cause some effect to occur
in the normally transparent areas. MReMapMode can be used with MBlitMode,
MQBlitMode, MSBlitMode, MQSBlitMode and MMaskScrollMode. MReMapMode is somewhat
slower than other blit modes due to the intensive processing required.