Refactored get_data/set_data-routines.
Added d2o_librarian.
Started work on updated unittests.

Started rework of the d2o slicing: introduced 0-dimensional advanced indexing capabilities.

Added some ufuncs to point_space, field and distributed_data_object.
Updated the projection_operator.

-> Many minor and major bugfixes
-> Reworked indexing (now works with negative step sizes, too)

Updated the naming of domain, codomain, target and cotarget in the spaces, fields and operators.
-> The propagator_operator is now 3 times faster

Reworked init of d2o.
Implemented a distributor cache.

Implemented interface for slicing methods in slicing distributors. fftw_distributor is now a special case.
Implemented flatten routines for d2o.

Added direct_dot to nifty_simple_math.py.
Begun with direct probing implementation.

Misc changes. Separation of field and space functionalities further improved. The fft of a field now runs purely with a distributed data object as it is now the natural data object of rg_space.

Added a mpi_dummy.py. Integrated the paradicts to the spaces. Implemented unary_operation, binary_operation and norm in the spaces. Extended the functions of the distributed_data_object for the unary and binary operations.