[GRASS5] moved numerical functions libgis -> libgmath

[Markus Neteler]

As a small contribution to the code cleanup I have moved
out some numerical functions from
 src/libes/gis/
to
 src/libes/gmath/

(files: la.c dalloc.c eigen_tools.c ialloc.c lu.c svd.c)

The motivation is to have all numerical stuff in one place: libgmath.

Several Gmakefiles have been updated to reflect the change
as well as Makefiles in GRASS 5.7 (there: run 'make mixclean ; make mix').

Hope it's still compiling (I've tested 5.3-static, 5.3-shared and 5.7-shared).
Otherwise please fix in CVS the new dependency on $(GMATHLIB).

I would welcome to see more numerical functionality moved from the modules
to libgmath. Hopefully we'll find someone ...

Cheers

 Markus