gnucsator & header locations

On Thu, Sep 23, 2021 at 06:34:38PM -0700, Dow Drake wrote:
> > Will fix this one shortly. But there may be more funny problems showing
> > up with two versions installed. Please let me know!
> 
> I pulled your last commit and reran ./configure and tried to make, but some of the gnucap headers aren't being found now:
> ```
> $ make -j4
> asking /home/dow/local/gnucap/install/bin/gnucap-conf
> make -C qucsator GNUCAP_CPPFLAGS="-I/home/dow/local/gnucap/install/include/gnucap -DADD_VERSION"
> make[1]: Entering directory '/home/dow/local/gnucsator/qucsator'
> g++ -c -fPIC matrix.cpp -o matrix.o -DNR_TINY=1e-15 -Dnr_double_t=double -DHAVE_STD_ERF
> g++ -c -fPIC vector.cpp -o vector.o -DNR_TINY=1e-15 -Dnr_double_t=double -DHAVE_STD_ERF
> g++ -c -fPIC complex.cpp -o complex.o -DNR_TINY=1e-15 -Dnr_double_t=double -DHAVE_STD_ERF
> g++ -c -fPIC real.cpp -o real.o -DNR_TINY=1e-15 -Dnr_double_t=double -DHAVE_STD_ERF
> In file included from matrix.cpp:94:
> logging.h:2:10: fatal error: io_error.h: No such file or directory
>     2 | #include <io_error.h>
>       |          ^~~~~~~~~~~~

this was one more of the same. fixed in develop.

> c++    -I. -std=c++11 -fPIC    -I/home/dow/local/gnucap/install/include/gnucap -DADD_VERSION -o lang_qucs.so lang_qucs.cc   -shared # 2
> In file included from vector.cpp:41:
> object.h:2:10: fatal error: e_model.h: No such file or directory
>     2 | #include <e_model.h>
>       |          ^~~~~~~~~~~

this one I don't understand. it should have found
/home/dow/local/gnucap/install/include/gnucap/e_model.h