(string) ucFirst                    ($haystack, [$delimiter = '_'])
                
    First word to capitalize, even if it was acronym.
Parameters:
| name | type | default | caption | 
|---|---|---|---|
| $haystack | string | String to Convert. | |
| $delimiter | string | '_' | Delimiter. | 
Returns:
- (string) — Capitalized String.
Author:
- StewEucen
Since:
- Version 1.0.0
Examples:
use StewEucen\Acts\IntactCase
IntactCase::ucFirst('highClass')       //=> "HighClass"
IntactCase::ucFirst('xml_HTMLRequest') //=> "XML_HTMLRequest"