[ADD] new progress decorator based on progressbar module

[ypapouin]

This is a first attempt to create a progress decorator.
It was not tested with OpenERP/Odoo Cursor class, I made my tests with the psycopg2._ext.cursor class.

It was discussed here:
OCA/OpenUpgrade#1897

[pedrobaeza]

Not sure about linking the bar with a row fetch, because progress bar will be associated usually with ORM operations, not with DB fetches. I think a decorator that links the call to a method and a total number would be better, so each time that method is called, you increase the counter.

[legalsylvain]

I think that both (orm operation & DB fetches) are valid and should be covered. (Maybe with two decorators, if a single one is not simple to implement.)

[pedrobaeza]

Supersede by #233