[imp]Project:Improve the usability in project stage form view and projec...

...t form view.

Task: https://www.odoo.com/web#id=10838&view_type=form&model=project.task&menu_id=3942&action=327
Pad: https://pad.odoo.com/p/r.hi9Pu2KGw5HZYcXp
With this you'll still get help after two blank line, the reason is _.map returns something like ["", "Some Help"], so join will convert ""\n\n"somehelp", you should use _.compact to remove blank and false values
Right now we are not getting groupby_tooltip title hence I also added key here
```this.tooltip =
                _.compact(_.map(
                    options.group_by_tooltip,
                    function (key, value, list) { return self.values && self.values[value] && (key+ "\n" +self.values[value]) || ''; }))
            .join('\n\n');```