Munipack update

I'd updated Munipack's configure.in to fit a "modern" way to search for fortran's 90 compiler by simply application of AC_PROG_FC macro.

This is a really great step, while last five years the compiler were detected by my own macro (four years ago) or by detecting of various specified compilers (up to today).

By the way, I'm suppose that Munipack compilation will more portable on modern distributions (Ubuntu?).

The macro's change will result in prefer of use of gfortran (not g95, ifc,..) compiler. One is pretty g95-compatible so it has implied changes in munilist's main and it remind me that the main is still non-wraped via C. I started rewrote it. The different compiler to compile can be specified via ./configure FC=ifc.

A problem has been reported under Mandriva Linux 2007.1 distribution. The compilation aborts with:

aflat_bin-autoflat.o: In function `MAIN_':autoflat.f90:(.text+0x8ce): undefined reference to `ftopen_'

(libcfitsio is installed corectly) which means that cfitsio is probally uncorrectly builded. The test with a simple C code is linked correctly, a simple code of fortran reveals the described problem. Specification of -fno-underscoring remove underscoring without expected effect.... (thx to petos).