docs: fixed esHelpers.R roxygen documentation.

[omarjcamanto]

85

esHelpers.R appeared to have exported functionality but did not have a @returns value. And so, I added a @returns and, just in case, a @examples tag to the esHelpers.R documentation.

Lastly, I can confirm that all internal, non-exported functions have @nord tags.

[codecov-commenter]

Codecov Report

All modified lines are covered by tests :white_check_mark:

Comparison is base (0ceb844) 80.06% compared to head (dd3e462) 80.06%.

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Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #87 +/- ## ======================================= Coverage 80.06% 80.06% ======================================= Files 20 20 Lines 3697 3697 ======================================= Hits 2960 2960 Misses 737 737 ``` | [Files](https://app.codecov.io/gh/jsakaluk/dySEM/pull/87?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=John+Sakaluk) | Coverage Δ | | |---|---|---| | [R/esHelpers.R](https://app.codecov.io/gh/jsakaluk/dySEM/pull/87?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=John+Sakaluk#diff-Ui9lc0hlbHBlcnMuUg==) | `0.00% <ø> (ø)` | |

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[jsakaluk]

@omarjcamanto: Out of curiosity, before I merge this, can you run devtools::check() to see if it's happy with the way this has been handled?Sometimes it will complain about the examples, so hopefully it comes back clean [or at least with unrelated issues].

[omarjcamanto]

I have run devtools::check() and it returned some notes that appear to be unrelated to the changes made in esHelpers.R.

I can try to resolve those devtools::check() notes if needed!

[jsakaluk]

Interesting. Some of those notes are new/surprising (e.g., it complaining about a license). Will circle back to this, but for now will merge.