Release version 2.4.0.1
Update tests to 2.4.0.8 style

This patch updates the test to the unittest based style as found in
other modules of Tryton.

Also bumps the version to 2.4.0.2dev
Migration to Active Record design pattern

* Also bump version to 2.6.0.1dev
Release version 2.6.0.1
Bump version to 2.6.0.2dev
Fixes to issues omitted while active record migration
Merge pull request #8 from shalabhaggarwal/develop

Fixes to issues omitted while active record migration
Resolved flake8 issues #2345

Task ID: project-989/task-2345
Review ID: 422002
Merge pull request #9 from prakashpp/feature/task-2345

Feature/task 2345
Bump version to 2.6.0.2
Merge branch 'release/2.6.0.2'