Rewrite Format-Hex on C#

[iSazonov]

As approved in #2718 Format-Hex should be rewritten on C#.

[iSazonov]

/cc @rkeithhill

[rkeithhill]

Where should this cmdlet's source go? I was thinking it would go in PowerShell\src\Microsoft.PowerShell.Commands.Utility\commands\utility\FormatAndOutput\format-hex\format-hex.cs? Is that the right place?

[iSazonov]

Yes. Looks good.