[backend] requirements: define deps for prod and dev.
[backend] created backend base structure.

The Django project is **techday**, it contains a **quiz** application.

These have been created using the commands:

```
$ cd backend/
$ django-admin startproject techday
$ cd techday/
$ ./manage.py startapp quiz
```
Ignore *.sqlite3 database file.
[backend] install ipython as dev dependency.
[backend] creates Person model with layout in admin.
[backend] created API for Person model.
[backend] API is allowed from all.
[backend] hook API entry points.
[backend] add a Makefile to clean some stuff.
Merge branch 'backend_prepa'

* backend_prepa:
  [backend] add a Makefile to clean some stuff.
  [backend] hook API entry points.
  [backend] API is allowed from all.
  [backend] created API for Person model.
  [backend] creates Person model with layout in admin.
  [backend] install ipython as dev dependency.
  Ignore *.sqlite3 database file.
  [backend] created backend base structure.
  [backend] requirements: define deps for prod and dev.