function removeFirst( str, n ) {
	return str.substring( n, str.length );
}
Removes the first `n` UTF-16 code units of a string.

@param {string} str - input string
@param {NonNegativeInteger} n - number of UTF-16 code units to remove
@returns {string} output string

@example
var out = removeFirst( 'last man standing', 1 );
// returns 'ast man standing'

@example
var out = removeFirst( 'presidential election', 1 );
// returns 'residential election'

@example
var out = removeFirst( 'JavaScript', 1 );
// returns 'avaScript'

@example
var out = removeFirst( 'Hidden Treasures', 1 );
// returns 'idden Treasures'