[Help] Compile xgrass on Motif 1.2

[H. J. Hong]

With the help from Raymond Venneker (venn at geo.vu.nl), I have successfully
installed Xgrass with Motif 1.2 on our SunOS4.1.1.  Although it is not very 
stable (sometimes it will terminate with some error message which
I donot know), it can show and display maps with a good interface. 
I list the procedure/changes I did for your reference.
---------------------------
     XmRStringArray was re-defined in Xm/XmStrDefs.h -> XmP.h -> Xm.h
                                   in grass4.1/source/src/include/Matrix.h
              comment out the one in Matrix.h
              not compatible with Motif1.2
              add #include <Xm/ManagerP.h> to xgrass/libes/Xgi/Matrix.c
              add #include <Xm/PrimitiveP.h> to xgrass/libes/Xgi/Clip.c
              add #include <Xm/ManagerP.h> to xgrass/libes/Xgi/Caption.c
              add #include <Xm/PrimitiveP.h> to xgrass/libes/Xgi/Interact.c
              can not link xgrass/menu; Undefined_symbol _MAX 
              add 
                 #ifndef MAX
                 #define MAX(a,b) ((a) > (b) ? (a) : (b))
                 #endif
                 into src/xgrass/libes/Xgi/Help.c. 
              add
                 #ifndef Max
                 #define Max(x,y) (((x) > (y)) ? (x) : (y))
                 #endif
                 #ifndef Min
                 #define Min(x,y) (((x) < (y)) ? (x) : (y))
                 #endif
                 to xgrass/xgbuffer/xgbuffer.c
              then, follow the instruction provided in the Installation Guide