Migrated to 2.8 and added Tests  #2366

Task ID: 2366

Review ID: 402001
Merge branch 'release/2.6.0.2' into develop
Merge branch 'feature/task-2366' of github.com:Abhisar/trytond-elastic-search into Abhisar-feature/task-2366
Bump version to 2.8.0.1
Merge branch 'release/2.8.0.1'