Remove unused classmethod and add docstrings
Provide models for activity handling
Add admin views for activity types configuration
Provide a main module for common forms elements

Here we will store:

* common schemanodes builders
* colander deferreds commonly used
* common widget builders
Use the tools provided by the new forms.main module
Add years utilities in the main module
Use the main module in commercial forms
Add the mail_input to the main module
Use the main module for customers forms
Further on with merging common tools in forms.main
Still cleaning
Move get_date_input globally
Provide a sqlalchemy utility to request users by role
Set Modes in a global var to be used in views
First shot for activity views
Ajax form specific tmpl
Rename the Event state to status for uniformisation
Little code factorisation
Add an helper for activity status formatting

This helper is available in templates with api.format_activity_status
Fix node builder's name

The newly created main module provide a today_node allowing to easily
create a form node schema for date configuration defaulted to today.