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Remove all references to private functions and symbols from the public
Fortran modules. Install also only the public modules

The QR decomposition test program can now called with parameters for
matrix size, nev, and block size.
This closses issue #20

Michael Bankd (debian) provided a patch, which allows
to run the qr-decomposition test programs with smaller matrices, and
thus allows testing in reasonable time on limited hardware (e.g. arm
devices)

In order to make the patch work, also Makefile.am was updated

Now this is done consistently both in autoconf and automake. One can now
safely call make clean and the header files are re-generated
automatically.

Automake does not easily allow to use the same source in a libtool
library and in a program

The issue why these test programs are simply not build
has to be investigated

It turned out that if a CPU supports SSE the already existing
test for SSE assembly instructions always passes.
However, the compilation of gcc SSE intrinic instructions might
nevertheless fail if gcc is not called with one of the options
"-msse3", "-msse4" , "-msse4.1", "-msse4.2", "-mavx", or "-mavx2"!

Obviously gcc does still not consider SSE as a standard on X86_64
Intel CPUs.

An additional configure test has been introduced, which test for
gcc intrinsic sse instructions. If this test fails, the corresponding
kernels are switched off.

The C++ kernels can be written as C kernels, which simplifies the build
procedure

In order to increase type safty all ELPA2 kernels provide now
an interface. The interfaces for the C/C++ kernels are automatically
generated during the configure step

The test programs are just needed at the build step (make check),
they are useless for users and will not be installed anymore

For the Intel compiler, this was assured with the pragma

  !DEC$ ATTRIBUTES ALIGN: 64:: a

however, other compilers such as gcc of course did not honour this,
which could result in SIGSEGVs in case the variable was not aligned to
32 bytes (by chance!).

This fixes issue #11, thanks to Nico Holmberg for reporting this.

The SSE kernels with blocking of 2,4,6 (real case) and 1,2 (complex)
case are now available by default

Thus the following changes have been done
- introduce new macros in configure.ac and Makefile.am
- renmae the AVX kernels in AVX_AVX2 (they also support AVX2)
- introduce new files with SSE kernel
- introduce new kernel parameters !
- make the SSE kernels callable

The results are identical with previous kernels

- The SSE part will be available in different files.
- Specify whether AVX or AVX2 was used to build

The test programs include the same template now, the
printed messages are thus unified

The configure flag "--enable-shared-memory-only" triggers a build
of ELPA without MPI support:

- all MPI calls are skipped (or overloaded)
- all calls to scalapack functions are replaced by the corresponding
  lapack calls
- all calls to blacs are skipped

Using ELPA without MPI gives the same results as using ELPA with 1 MPI
task!

This version is not yet optimized for performance, here and there some
unecessary copies are done.

Ths version is intended for users, who do not have MPI in their
application but still would like to use ELPA on one compute node

The generic real kernel is now contained in a module, this allows
strict interface checking! It also does not use assumed size arrays
anymore. Both points increase the possibility to debug and find errors.

However, this might be performance critical! It is possible to
switch back to the old implementation if that turns out to
be beneficial w.r.t. performance. Timings with gfortran 4.9 on Intel
Haswell showed that the new implementation is about 30 percent faster
then the previous one

Now all functions, which were "contained" in anoter one are moved
to seperate modules. This allows for strict interface checking and
debugging

This routine has been contained in a subroutine.
It has been moved to a module and and renamed to
"single_hh_trafo_real" to make it's intention more clear

The Fortran variable declerations "variable type*[4,8,16]" is non
Fortran standard. It might cause problem in the future.
Furthermore, the usage of Fortran and C togehther is more clean
if variables are defined according to C variable types.

This is done, now for all the test programs

This commit does not change the interfaces defined in ELPA_2015.11.001 !
All functionality is available via the interface names and definitions
as in ELPA_2015.11.001

But some new interfaces have been added, in order to unfiy the
references from C and Fortran codes:

- The procedures to create the ELPA (row/column) communicators are now
  available from C _and_ Fortran with the name "get_elpa_communicators".
  The old Fortran name "get_elpa_row_col_comms" and the old C name
  "elpa_get_communicators" are from now on deprecated but still available

- The 1-stage solver routines are available from C _and_ Fortran via
  the names "solve_evp_real_1stage" and "solve_evp_complex_1stage".
  The old Fortran names "solve_evp_real" and "solve_evp_complex" are
  from now on deprecated but still functional.

All documentation (man pages, doxygen, and example test programs) have
been changed accordingly.

This commit implies a change in the API versioning number, but no
changes to codes calling ELPA (if they have been already updated to the
API of ELPA_2015.11.001)