[GRASS5] Imagery Library memory allocation cleanup questions

Hello all,

Is it okay to remove these from lib/imagery:
- I_malloc()
- I_realloc()
- I_free()

I_malloc() is unused. I_realloc() and I_free() are used by a single
file and easily changed to G_realloc() and G_free().

And move these to lib/gis:
- I_alloc/free_double2()
- I_alloc/free_int()
- I_alloc/free_int2()
- I_alloc/free_double3()

These four functions are only used in lib/imagery/c_execmem.c at the
moment.

If there are no objections, I'll submit a patch.

--
Brad Douglas <rez@touchofmadness.com>