Performance improvements for host.create, template.update. templates linking process, DB::insert() method

Sprint 74 (Mar 2021), Sprint 75 (Apr 2021), Sprint 76 (May 2021), Sprint 77 (Jun 2021), Sprint 78 (Jul 2021), Sprint 79 (Aug 2021), Sprint 80 (Sep 2021), Sprint 81 (Oct 2021), Sprint 82 (Nov 2021), Sprint 83 (Dec 2021), Sprint 84 (Jan 2022), Sprint 85 (Feb 2022), Sprint 86 (Mar 2022), Sprint 87 (Apr 2022), Sprint 88 (May 2022), Sprint 89 (Jun 2022), Sprint 90 (Jul 2022)