Issue Labels and Contributions in NLTK

[liling tan]

NLTK issues have been growing and a couple of minor releases has been made this year.

We're starting to better utilize the labels on the Github to encourage contributions and anyone who wants to comment/review on relevant issues.

If anyone is looking for contribution opportunities, there issues labelled as "good first bug" https://github.com/nltk/nltk/labels/goodfirstbug that can be easily patched, e.g.:

 - Documentation issues:

   - https://github.com/nltk/nltk/issues/1817

   - https://github.com/nltk/nltk/issues/1708 

 - Corpus related issues:

   - https://github.com/nltk/nltk/issues/1384

   - https://github.com/nltk/nltk/issues/1457

For more challenging issues, there's the "bug" and "enhancement"

 - https://github.com/nltk/nltk/labels/bug

 - https://github.com/nltk/nltk/labels/enhancement

And for those looking to contribute more, the "nice idea" label usually tags the issues that might require more time/effort: https://github.com/nltk/nltk/labels/nice%20idea

Corpora / Models are also welcomed and here's a quick guide on how to add a corpus to NLTK https://github.com/nltk/nltk/wiki/Adding-a-Corpus

We'll guide you along the way once you start an issue or PR to the repository =)

One last special request is for any brave soul(s) who would like to work on NLTK officially supporting Python3.6 https://github.com/nltk/nltk/issues/1659

Other than contributing code, comments / thumbs-ups / suggestions / code reviews are very welcomed too.

We are encouraging inputs to issues / PRs that might need some triage and/or advice.

This issue that attempts to garner discussion might be of interest too: https://github.com/nltk/nltk/issues/1846

We thank all of you that have contributed to NLTK!!