Primeng: Support for Both Font Awesome 4 and 5

[jallison95]

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I have updated my solution to use FA 5. I had to modify some of the prime NG comonents

FA5 no longer supports the alias names.
fa-close = fa-times
fa-warning = fa=exclamation

These are the issues i have found so far. The changes would allow to use both FA 4 and FA 5

https://forum.primefaces.org/viewtopic.php?f=35&t=53211&p=161938#p161938

[FrancesCoronel]

In the meantime, I'm just defining the Unicode characters for those aliases in the SASS files like this:

.fa-close:before {
  content: '\F00D';
}

[cagataycivici]

See;

https://github.com/primefaces/primeng/issues/5098