[Ml-yokadi] utils.py is no more

[Aurélien Gâteau]

Hello,

I just finished splitting utils.py. Most of it is in dbutils.py, the 
rest has been moved as discussed before in completers.py and project.py.

I also added a few unittests. We still do not have full coverage, but 
there is at least now a test for t_add, for some completers and for 
p_rename. This strange choice of tested features comes from the fact 
that I added tests for methods I needed to rework while splitting utils.py.

I also got rid of TextRenderer.

Here is my TODO list for the release:
- Doc update system
- Write a README, getting started doc
- Test github automatically generated tarballs
- Create website

Aurélien