Italian application added. Minor bugs corrected.

I've installed mapit, using the git URL in the requirements as a django application within a pre-existing project.
I modified the .gitignore to include the ``django_mapit.egg-info`` path, automatically created.

The mapit_it application has been added, with a management task to find parents of the official ISTAT administrative subdivisions and an adapted zip code validation. It is just a prototype and other functions and tasks will follow soon.

Two minor bugs require revision, but I could not make separate pull requests (sorry)

  - 2bb188e - a string emitted to stdout as log was causing a unicode error (django 1.6.8 over python 2.7.7)
  - f7dde4c - cache value injection in a new key was cast to int; the string caused an error to the following incr instruction (cache engine is LocMem, while development)