make doc will now generate html&latex documentation

Changed .eq. to .eqv. for comparison of logicals
Changed assignment of logical to integer variable

Made vdW stuff in vgen dependend on CMAKE variable Fleur_uses_vdW to avoid compilation if no fftw is present
Added CPP_MPI dependency in eig66_mpi and initParallelProcesses to enable compilation of serial versions
Made initParallelProcesses a F90 file

Note: This is incomplete.

Missing: 1. vacuum energy parameters
         2. alternative types of energy parameters

Also in this commit: Changed the Htr to eV conversion factor
according to the 2014 CODATA recommended value.

and MPI, mem & DA versions

Also in this commit: Improved layout for out.xml output of
total energy contributions.

Note: This commit also introduces formatted output to out.xml.
It is not yet complete and not yet fully used for the small
test output of total energy contributions in this commit.

changed again for reasonable performance

The problem was probably caused by some variables not being
initialized.

Note that there are still some known issues:

1. Possibly incorrect data for energy parameters, LOs
2. Incomplete data: electron configuration, comment
3. Not neccessarily explicit data: Bravais matrix

changed phas(n) in spgrot.f to cc. Use cc of pgfft in pwden.F90,
partially in fft(3,2)d(xc).f90, and of phas in cdnovlp.F90.
Introduce complex phase & derived variables in q_int_sl.f90, hsint.F90,
vacfun.f90, potdis.f90. Initializations in strgn.f90, real arguments
for dot_product() in pwint(_sl).f90 & phasy1.f90. Stop message in
rw_symfile.f changed to 'complex phases not fully tested'.

This commit also provides helper routines to write out data into out.xml.
Nothing is tested yet. The routines might be horribly wrong.

Note that there are still bugs.

first_glance.f to read in l_gamma (w/o hybrid).
Updated atom_sym.f, crystal.f, inpgen.f90, lattice2.f, setab.f, and
struct_input.f for "Examples sorted by Bravais lattice" on web-page.

It is tested with the Yb example from the homepage.

This is introduced to guarantee that inp.xml can always be validated
against the Schema file belonging to the right fleur version.

To transform the atom positions in atom_sym.f into the centered basis,
a variable (i_c) is passed through to indicate the type of centering.

r_inpXML included a call to setlomap. This subroutine has the side effect
to reinitialize ulo_der to a value according to the definition in the old
inp file. I removed the call to setlomap and included the missing other
initializations directly in r_inpXML.

Note that there is still a bug in the LO setup iff multiple LOs with same
l quantum numbers are defined for the same species. Fleur has the rquirement
that the LOs are ordered with respect to the l quantum numbers. This ordering
is not yet performed in r_inpXML.