Add examples to functions

[DrMattG]

Added a few examples to functions (linked to #117)

compare.R
dedup.R
runShiny.R

I am not sure if the format of the examples is correct - I have used:
if (interactive()) { }

[TNRiley]

@LukasWallrich @DrMattG I may need some assistance understanding things here. Would love to get a run through on what happened here. Also on examples in general. I understand why my examples which I removed railed CMD, but have a few questions.

[LukasWallrich]

I just chatted with @TNRiley about this, and he will add a unique_citations dataframe to the package data that we can then use in all examples (and also for testing). So let's maybe put this on hold until we have that data.

Instead of interactive(), I would wrap examples that should not be run into

\dontrun {

}

That makes the intention clearer, but should be rather rare - maybe we want to use it for the import functions to avoid having to also provide ris files, but everything else should probably have working examples (export functions can easily write tempfiles ...)

[TNRiley]

I've been working on this and made some mistakes, but learning. It looks like interactive() is the recommended way to wrap examples rather than \dontrun - from the HW packages book. I'm still unsure about the best practice of when to include interactive() vs. not, however. Hopefully, I can get these @exmaplesfigured out soon to fix this CMD check.

[DrMattG]

Changes made in main.