DotDict moved to dune.common
As said, I think that an ini file parser/data structure that handles ini files exactly the way that the dune-common C++ classes do is a general nice to have for the python package dune.common. I have moved it over there. Btw, I do not agree that meta ini stuff belongs there right now.
Need to work with dune-python master.
This fixes #93 (closed)