* Update the vis.js framework to latest stable version (v4.20.1) to add new functionality and save almost
400ko of source code in odoo assets (the vis dev team has isolate the code for timeline widget from the
rest of their widgets)
* Add the possibility to display events with no duration (instantaneous) as the same time has regular events
* Add the possibility to choose between two scroll mode :
- zoom in time resolution (default)
or
- vertical scroll (web browser default behaviour)
Signed-off-by: adrien.didenot <adrien.didenot@horanet.com>
