How to Update the GDAL Tree with the new MG4 Lidar Driver

First note that currently we build as a separate (from the Raster MrSID) driver.
At some point in the future we intend to merge our SDKs.  At that point we
should merge the two drivers into one.

Changes / additions:
- nmake.opt
- frmts/mrsid_lidar/*.html
- frmts/mrsid_lidar/gdal_MG4Lidar.cpp
- frmts/mrsid_lidar/GNUmakefile, GDALmake.opt (not done)
- frmts/mrsid_lidar/makefile.vc
- frmts/makefile.vc
- frmts/gdalregister.cpp
- gcore/gdal_frmts.h

Noted defect:  If you build both MRSID and MRSID_LIDAR support then a reference 
   to a lidar file gets picked up by the raster driver and fails (Pilot error?)

I tested this build procedure on stable build GDAL v7.1.

I verified the resulting library by exercising gdalinfo and gdal_translate on 
the sample MG4 file (included).