Improve Developer experience (mostly ERP5 Workflow/Python Scripts)

Fixes [#20210517-960A47](https://erp5js.nexedi.net/#/bug_module/20210517-960A47)

The most important changes are:
 - coding style is enabled again for workflow scripts and starts to be enabled for ERP5 Python scripts
 - monaco editor support for workflow scripts, SQL methods and .less
 - small fixes for python/workflow scripts forms and ZMI

See merge request !1422
9 jobs for master in 0 seconds
Status Job ID Name Coverage
  External
passed ERP5.CodingStyleTest-Master

01:57:40

passed ERP5.PerformanceTest-Master

00:24:01

failed ERP5.UnitTest-Master

02:51:30

failed ERP5.UnitTest-Master.Medusa

01:52:14

canceled ERP5.UnitTest-TesseractVersionUp

00:28:26

passed SlapOS.Eggs.UnitTest-Master.Python2

00:08:10

passed SlapOS.Eggs.UnitTest-Master.Python3

00:16:39

canceled ERP5.UnitTest-TesseractVersionUp

canceled ERP5.UnitTest-TesseractVersionUp

00:18:04