Make a JSON file for runtime options

[Feat-FeAR]

The JSON should contain (at least) the following options for panc_profiler.R:

exclude_samples <- c("PANC1.4.days.pH.6_6.7_5_R_TPM.Acute", "PANC1.pH.selected.17_R_TPM.Select")

y_limit <- 10
border <- FALSE
thr <- 1