Fixed calculation of projection for STAR and/or SORI

Fixed calculation of projection for STAR and/or SORI

Both for STAR and for SORI, if provided to make_edi, the
fit structure and the average structure can be the same
(in these cases the old code works fine), or one can do
the fit on another (possibly larger) part of the molecule.
In the latter case, STAR (or SORI) contains first the fit and
then the average structure (concatenated). Here, the fit has to
be performed using the fit structure while the projection(s) have
to be calculated using the average structure. This is now
taken care of by the 'avindex' index variable.

Change-Id: Id97235030f3394df2931e30249083ad439dbe791