Move sfactor.[hc] to gmxana

Move it here since its only used by g_saxs

Change-Id: I2ff7761da30eabb569e55362cdc55d683b296d8e
Signed-off-by: Alexey Shvetsov <alexxy@omrb.pnpi.spb.ru>

diff --git a/src/gromacs/gmxlib/sfactor.c b/src/gromacs/gmxana/sfactor.c
similarity index 100%
rename from src/gromacs/gmxlib/sfactor.c
rename to src/gromacs/gmxana/sfactor.c

diff --git a/src/gromacs/legacyheaders/sfactor.h b/src/gromacs/gmxana/sfactor.h
similarity index 100%
rename from src/gromacs/legacyheaders/sfactor.h
rename to src/gromacs/gmxana/sfactor.h