Bootstrap 5.0 support

Added

• Add Bootstrap 5 floating labels via the floatingLabel() method for <input>, <select> and <textarea> tags

  NOTE: You need to use floating label elements with a vertical_open Former instance!

  Usage with Laravel:

  {!! Former::vertical_open() !!}
      {!!
          Former::text('test-floating-label-ok')
              ->placeholder('dummy placeholder')
              ->floatingLabel()
      !!}
      {!!
          Former::select('users-floating-label')
              ->options(['User One', 'User Two', 'User Three'])
              ->placeholder('Select placeholder')
              ->floatingLabel()
      !!}
      {!!
          Former::textarea('textarea-floating-label')
              ->floatingLabel()
              ->placeholder('dummy placeholder')
      !!}
  {!! Former::close() !!}
  
  {!! Former::vertical_open() !!}
      <div class="row">
          <div class="col">
              {!!
                  Former::text('test-floating-label-one')
                      ->placeholder('dummy placeholder')
                      ->floatingLabel()
              !!}
          </div>
          <div class="col">
              {!!
                  Former::text('test-floating-label-two')
                      ->placeholder('dummy placeholder')
                      ->floatingLabel()
              !!}
          </div>
      </div>
  {!! Former::close() !!}

• Add the switch markup which is a custom checkbox for Bootstrap 5

  Some use cases with Laravel:

  {!!
      Former::switch('valid_switch_ok')
          ->text('Valid switch OK')
  !!}
  
  {!!
      Former::switches('valid_inline_switches_ok')
          ->switches('first', 'second', 'third', 'fourth')
          ->inline()
  !!}

• Add removeGroupClass() and removeLabelClass() methods

  Usage with Laravel:

  {!!
      Former::text('test')
          ->removeGroupClass('row')
          ->removeLabelClass('foo')
  !!}

  WARNING: There is a bug in the HTMLObject package!
  See my pull request for more info: Anahkiasen/html-object#34