Add 'Other resources'

[unixorn]

shellcheck is a great resource for shell script newbies since it will call out dangerous and/or deprecated practices in their code.

Closes #59

[unixorn]

What section would you prefer me to add shellcheck to? Or should I leave it as a new section and rename the section something other than 'Other Resources?'

[denysdovhan]

I think it's better to add some links, for example:

• https://github.com/awesome-lists/awesome-bash
• https://github.com/denysdovhan/learnyoubash
• http://stackoverflow.com/questions/tagged/bash
• etc

In that case Other resources looks good to me.

[unixorn]

Added a few more resource links so shellcheck isn't lonely :smiley:

[unixorn]

I should have thought of dotfiles.github.io myself, I'm one of the maintainers :-)

[denysdovhan]

LGTM

[denysdovhan]

Published as v2.4.0! :+1: Thank you a lot!