in g_rmsf, residue averaging with -res is broken
when calculating rms fluctuations of atom positions with g_rmsf,
residue averages selected with -res are not produced.
Instead the value for the last selected atom in each residue is written.
The same applies to isotropic beta factors.
Rms deviations selected with -od are not affected.
In gmx_rmsf.c, the function average_residues() is called for the field
rmsf at line 360, before values for atom fluctuations are copied
from U to rmsf at line 366.
When output is produced, the value for the last atom is written,
where the residue average would have been stored.
Moving the assignment before of the averaging fixes the problem.
Output for -od is calculated separately,
and anisotropic beta factors are not averaged.