Add rodent census 541 data [minor]

[grilledlambchops]

Updating to include rodent census data 541

[gmyenni]

The new moon numbers may not be adding correctly if you don't have the latest version of main. Did you start this branch using the latest version of main?

[grilledlambchops]

I'm pretty sure I did. From the repo, I created a new branch rodents_541 with the source from main. And on my local machine, I pulled which in main and in branch 541. Both say they are up to date. Is there anything else I should do?

[gmyenni]

Okay, run the new_moon_numbers.r script locally and see if you can figure out what is going wrong.

[grilledlambchops]

I ran the new_moon_numbers.r script, no errors occurred. Then ran the new_rodent_data.r script again and committed.

[gmyenni]

Found the problem. The new moon script fetches official new moon dates using the lunar package. It adds them as they occur to the moon_dates.csv. Then, when the rodent data are added, it fetches those dates again to pair the new period with the closest unassigned new moon. Which shouldn't be a problem, they should be exactly the same. But I think, especially once the new moon is far in the past, it may arbitrarily choose one day or another when it spans both. So I've just switched that section of the script to use the new moon date from the moon_dates.csv, instead of recalculating it when it already exists.