Add r packages for waddenzee flavor

[gpelouze]

We need to create an R flavor with this env: https://github.com/LTER-LIFE/dtR/blob/upstream/Qing-environment.yml

Two options:

• create new r flavor (lighter images)
• add to existing flavor, that would support Py and R (easier to use: no switching between flavors)

[gpelouze]

• rename lter-life-wadden-py to lter-life-wadden
• add r dependencies there