+more cleanup

Changed layout of types, added first implementation of forcetheorem-type for MAE (test still missing)

...also in this commit: global/constants.f -> global/constants.f90

-removing of variable icorr, use of member-functions instead
-removal of icorrkeys module
-removal of hybridmix module
-cleanup at several places

Note: The Wannier code is not yet connected to the main code

I adapted Roman's code slightly such that it fits into the new fleur version.
Nothing is tested yet, so testing and polishing still needs to be done.

- made l_zref a local variable no longer in type sym
- changed the setup of the parallelization (mpi/mpimakegroups is obsolete)
- added new command line switches yet to be documented :-)

...to make inpgen compilable again after the last commit.

Added debug option to configure script
TODO:
ELPA version on JURECA can not be used. Interface of ELPA is changed :-(

Since the routine brzone featured many bugs that occured in special
cases I now reprogrammed the functionality of the routine in the
new subroutine brzone2. The new algorithm is simpler and should
be less vulnerable to the mentioned special cases. It also is slightly
slower. The new routine takes about 2 seconds.

By commenting the new routine out and the old one in both algorithms
can directly be interchanged.

configure.sh script is doing part of the job now
more details should be found in README (later :-) )

Removed preprocessor switches CPP_SOC, CPP_INVERSION, CPP_APW, CPP_CORE.
Only a single fleur executable is built.

A new file was missing in the associated cmake dependency list.