During release we need to create several update guides

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Create 6.0-to-7.0 update guide
The Wall is deprecated in 7.0
Merge branch '6.0-to-7.0' into 'master'

Create 6.0-to-7.0 update guide
Fix permission issue with highest access level for group

If user was a member of both group and project and group access level
was higher it was not respected and user got lowest project access
level. Now it is fixed and user get highest access level

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Merge branch 'update-guides' into 'master'

Mention all update guides in monthly release doc

Fixes #1328
Remove milestone observer from db fixture.
Merge branch 'fix-permissions' into 'master'

Fix permissions

Fixes #1358
Bump version to 7.0.0

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>