Update Font Awesome icons version

[timeverts]

This is a great package. Thanks for your work. Any chance you could update it to use a more recent version of Font Awesome?

There's now a heap more icons available as Font Awesome version 5 is up to 5.15.4 and there's also a version 6 (the current version).

[timeverts]

@marisks, just wondering whether you have any capacity to implement these updates?

[marisks]

Sorry, but no, not in near future.