[GRASS5] added test for LAPACK/BLAS in configure[.in]

[Markus Neteler]

Hi,

as some more work is to be done to eliminate the "Numerical
recipes in C" functions from GRASS, I have added a test to
configure configure.in src/CMD/head/head.in

for LAPACK/BLAS libs (used for src/libes/gmath lib).

The idea is to move all numerical functions from the individual modules into
gmath lib (especially from the image processing modules). Perhaps the gmath
lib shall be splitted into basic functions not needing the LAPACK/BLAS (from
www.netlib.org) and a fully featured gmath lib with LAPACK/BLAS support.
gmath currently operates as a wrapper to LAPACK/BLAS (written by David D.
Gray).

Please let me know if the configure changes break anything.

Thanks,

 Markus