Using warning() instead of print()?

[paocorrales]

Hi! I'm happy to see this package alive again!

I've used some of the code to calculate the spi for another package and now we'll be able to add SPEI as a dependency. One thing I realize while doing some tests is that you are printing the warnings you collect in the spei() function using print() and that generates a lot of text in the console. I know you can avoid that by using verbose = FALSE but I think that using the warning() function instead of print() is a better practice, that way, R will recognize the text as a warning instead of random text.