names of "module binaries" do not convey "feff8l"-ness

[newville]

Currently (unless I'm mistaken), make install installs

• PREFIX/bin/: ff2x, genfmt, pathfinder, pot, rdinp, xsph

• PREFIX/lib/: json_module.mod, libfeffpath.EXT, libfeffphases.EXT, libjsonfortran.a, libonepath.EXT, libpotph.EXT

• PREFIX/include: feffpath.h, feffphases.h

where EXT='so' for linux, 'dylib' for Mac, 'dll' for Windows.

I see three problems here:

1. there actually isn't a "feff8l" script or executable.
2. there really isn't anything that clearly identifies these as belonging to "feff8l".
3. it's not really clear to me why there are so many "feff8l libraries".

I propose condensing the shared libraries libfeffpath.EXT, libfeffphases.EXT, and libonepath.EXT
to a single libfeff8l.EXT, and changing the name for the installed binary files:

bin/ff2x -> bin/feff8l_ff2chi
bin/genfmt -> bin/feff8l_genfmt
bin/pathfinder -> bin/feff8l_pathfinder
bin/pot -> bin/feff8l_potentials
bin/rdinp -> bin/feff8l_readinp
bin/xsph -> bin/feff8l_phases

We can then also include a bash file (or bat file for Windows) that runs all of these.

[bruceravel]

I don't know that it was a good decision, but my thinking behind the libraries is that libonepath and libpotph are the Fortran entry points. That is, a Fortran programmer would want a familiar, Fortran-syntax way of getting into those two things. They both expose Fortran subroutines with a long argument lists.

libfeffpath and libfeffphase are fairly thin C wrappers which expose a data structure and map the data structure onto the Fortran subroutine calls in the other two libraries.

As I said, not necessarily the most sensible, but it's what I did when i did it, which was quite some time ago by now....

As for the executables, I replicated what Feff8 did as delivered and thought about improving upon it not at all. That wasn't a decision so much as a stopping point.

I am fine with executables named feff8l_*. I would also be fine with a small C or python program called feff8l which, when called without an argument, would run all of Feff in the original sense. When called with an argument, it would run the individual steps.

[newville]

addressed in #41, though the small feff8l program there is in Python (with no non-standard lib dependencies).