Convert base/fit to new GF

  renamed:    pytriqs/base/fit/fit_test.py -> doc/user_manual/data_analysis/fit/fit_test.py
  deleted:    pytriqs/base/fit/fit1.py
Fix for issue #116, Failed DFT tests
Add pade approximants

The old files have been reorganized. The pade_appximants class is put
in the triqs/utility directory. The gf-related pade() function is in
triqs/gf/local.

  new file:   triqs/utility/pade_approximants.hpp
  new file:   triqs/gf/local/pade.cpp
  new file:   triqs/gf/local/pade.hpp
Add set_from_pade in python gf refreq

Checked in a notebook. Seems ok.

  modified:   pytriqs/base/gf/local/functions.pxd
  modified:   pytriqs/base/gf/local/refreq.pyx
Fix misc stuff to have doc compiling

  modified:   doc/user_manual/green/block/green_pade.py
  modified:   pytriqs/base/__init__.py
  modified:   pytriqs/base/dos/hilbert_transform.py
  modified:   pytriqs/base/fit/__init__.py
  modified:   pytriqs/base/version.py.in
  deleted:    pytriqs/base/info.sh
Adapt pade test

Should now be a bit more robust against architectures and compilers.
Also modify slightly the documentation.

  modified:   doc/user_manual/green/block/green_pade.py
  modified:   pytriqs/base/test/pade.output.h5
  modified:   pytriqs/base/test/pade.py
Adapt GF python tests

  modified:   pytriqs/base/test/gf_base_op.output.h5
  modified:   pytriqs/base/test/gf_base_op.py
  modified:   pytriqs/base/test/gf_init.output.h5
  modified:   pytriqs/base/test/gf_init.py
Fix #118 : hdf5 HL for old version of cmake
arrays : add MutableConcepts, clean matrix assign

- add MutableVector, MutableMatrix, MutableArray

- move the specialisation for matrices into the
assignment::impl class, so that it automatically
ok for matrix, matrix_view and any new class that
would model MutableMatrix.
--> in particular scalar assignment, scalar +=, -=

- deletion of *=, /= for non scalar moved back as
static_assert (interception) into the assignment::impl
class.
ctqmc_hyb: fix unused variable warnings

- as said by clang -Wall
doc : fix array cookbook

change = to <<
utility : factory improvement
arrays : minor fix on doc
arrays : change call in concept, simplify foreach

- moving the concept to full variadic
remove the key call with [] and replace with variadic call (was
almost done before)
- rewrite the foreach : move it simply in the domain :
only one version, the variadic one.

-clean and comment indexmap_storage_pair

- remove test of array of dim 9
-> test construction of large arrays .. to do
arrays: clean the const T construction pb

- assignment to array<const T> is forbidden,
with a better error message.
- construction of an array, matrix, vector
from a const T is however possible.
-> using another assignment op 'F' which remove the cast,
only called in the constructors...
-> replace the previous horrible hack ...
arrays : add move constr, = to views

- added move constructor, = for view, needed by sliding_view
- corrected left cout in domain
gf: squash many dev commits
gf: remove bracket evaluator

- [] only for mesh_index_t
since it has const and not const version, it is quite different
from () operator which is *always* const.
- For blocks, it does not change anything (only use at the moment).
- removing last "target"
gf: made gf_factories
introduce utility/macros.hpp to regroup macros..

- ENABLE_IF and co
- DECL_AND_RETURN