[ADD] added rating, rating_project and rating_project_issue module

 - Task : https://www.odoo.com/web#id=8060&view_type=form&model=project.task
 - Pad : https://pad.odoo.com/p/r.2BmKqyvcwKbiXPRI

[IMP] Added option to install rating module under Project

[IMP] added template to display when customer rates the task/issue

[IMP] Improved template and code

[IMP] : rating , rating_project and rating_project_issue as per new api

[IMP]: rating template

[FIX] : test case failed

[IMP] : code
No,  because `_get_happy_customer` is used to calculate total percentage happy customer of task and issue both ,  and it actually work on check box(use task, use issue on project form by default true if module is installed) whichever is true calculation done base on that, while `_percentage_count_task`  is only calculate percentage of task , same method is for issue in rating_project_issue module '_percentage_count_issue'(is used to display on project form as stateinfo button)