[ADD] note: Adding 'Share' column for followers of the note.

Task: https://www.odoo.com/web#id=10795&view_type=form&model=project.task&action=327
Pad: https://pad.odoo.com/p/openerp-project.task-OAKV36MWN5

Description: 
[FIX] note: Fixing issue of Two 'This weeks' stagies for Administrator user.
[ADD] note:
1- 'Shared' stage for user to identify notes which are not created by him/her but added as follower.
2- Stage named 'New' for Demo user.
Thank you for a brave suggestion! I have changed accordingly.