(1.)
Renamed function err() to declare_error().
This was a problem, as many standard libraries also has functions err().

(2)
I fixed a lot of compiler warnings like unused variables and uninitialised variables. However, here is a lot of work to do.

The readmod functions verify now the dimension of the model file. Therefore IFOS will abort, if the model file is to small or too big.
Moreover, the write_matrix_disk function is used to write the models to disk.

INVMAT - > FORWARD_ONLY
INVMAT1 - > PARAMETERIZATION

! This commit renames DENISE to IFOS !
Keep care and update all of your self written shell scripts etc.
The make target is 'IFOS' (capital letters).
The resulting binary is called 'IFOS' as well.

Update: Merge test