Review and clean CO2 functions

[sarah-gao]

In the current workflow, I use the find_peaks.R function (https://github.com/ZimmermanLab/gao-thesis/blob/main/code/functions/co2_functions/create_std_curve.R) to calculate areas under the curve for each CO2 measurement. I then use the create_std_curve.R function (https://github.com/ZimmermanLab/gao-thesis/blob/main/code/functions/co2_functions/create_std_curve.R) to calibrate these AUCs into CO2 ppm values.

Currently, the create_std_curve.R function is broken and doesn't work within the compile_data.Rmd flow. I think this is mostly due to some variable name changes I made recently, but also it needs major clean up in general.

Both scripts originated from Jacob Anderson's repo with heavy modifications from me: https://github.com/andersonjake1988/peak.gas

[naupaka]

I've been working through these but have some questions -- we can discuss when we meet.