[EPIC] Allow selection of resources via URL parameters

[yuvipanda]

Part of #4109

Description

As part of #4109, one of the acceptance criteria is for the creator of the link to:

Ability to select what kinda resources the Reader receives when they click the link

This requires us to be able to embed resource requests of the launched server in the URL of the 'binder' link, in a standardized way.

Tasks

This would most likely require re-enagaging with the following upstream tickets

• Select pod resources from binder UI jupyterhub/binderhub#731
• Query parameter naming scheme? jupyterhub/binderhub#712
• Custom resource requests jupyterhub/binderhub#759