Revision 136

Clarified the logic in filtreg by creating a procedure
filtreg_hemisph. It was terrible with a loop on hemispheres and tests
on hemisphere inside the loop, plus maddening indirections on latitude
bounds, plus repeated code. Went from 126 lines to much clearer 74 +
32 = 106 lines.

In module inifilr_m, finally made the arrays matrice[uv][ns],
matrinv[ns] dynamic (following LMDZ). Changed the lower bound of
matriceun and matrinvn in the 3rd dimension: 2 instead of 1, the index
1 was not defined (nor used).

In module inifilr_m, changed the bounds of matriceus and matrinvs in
the 3rd dimension: jfiltsu:jjm instead of 1:jjm - jfiltsu + 1. Changed
the bounds of matricevs in the 3rd dimension: jfiltsv:jjm instead of
1:jjm - jfiltsv + 1. It is a little simpler and clearer this way in
procedure inifilr.