Compile existing GitHub accounts with DevSummit content

[hhkaos]

There are presenters and teams that have been using their own GitHub personal accounts for years to host the code samples and slides. For example:

https://github.com/ekenes/conferences by @ekenes
https://github.com/ycabon/presentations by @ycabon
https://github.com/tomwayson?tab=repositories&q=dev&type=source&language=&sort= by @tomwayson
https://github.com/odoe?tab=repositories&q=ds&type=source&language=&sort= by @odoe
etc.

FInd more...: https://esri-es.github.io/arcgis-experts/

We should find a nice way to make these sessions discoverable from here. Maybe fork them, maybe just create in the main README file a reference to another markdown page with all these presenters that are hosting their resources somewhere else.

[hhkaos]

Adding that the python team also usually upload theirs here: https://github.com/Esri/arcgis-python-api/tree/conference_talks/talks