function upperCase(subject) {
    var subjectString = coerceToString(subject);
    return subjectString.toUpperCase();
  }
Converts the `subject` to upper case.

@function upperCase
@static
@since 1.0.0
@memberOf Case
@param  {string} [subject=''] The string to convert to upper case.
@return {string}              Returns the upper case string.
@example
v.upperCase('school');
// => 'SCHOOL'