erp5_web_service: Add mixin component to use RESTAPI

See merge request !1872
6 jobs for master in 0 seconds
Status Job ID Name Coverage
  External
passed ERP5.CodingStyleTest-Master

00:40:26

failed ERP5.UnitTest-Master

01:19:14

failed ERP5.UnitTest-Zope2

01:14:00

passed SlapOS.Eggs.UnitTest-Master.Python2

00:14:27

passed SlapOS.Eggs.UnitTest-Master.Python3

00:16:22

failed Wendelin.UnitTest-Master

00:39:28