erp5_run_my_doc: add slideshow editor gadget

This gadget only works in ERP5JS, as it depends on multiple ERP5JS only gadgets.

Some functionnalities have not been backported for now:
* image upload, which seems broken on xhtml style
* test template (I was not able to trigger something from the UI)

Normally, it could be possible to create an OfficeJS app with this editor.
7 jobs for master in 0 seconds
Status Job ID Name Coverage
  External
passed ERP5.CodingStyleTest-Master

01:44:01

passed ERP5.PerformanceTest-Master

00:33:04

failed ERP5.UnitTest-Master

02:36:26

passed SlapOS.Eggs.UnitTest-Master.Python2

00:22:10

passed SlapOS.Eggs.UnitTest-Master.Python3

00:23:13

passed SlapOS.Eggs.UnitTest-Master.Python2

00:39:35

passed SlapOS.Eggs.UnitTest-Master.Python3

01:55:40