added options wrapperParent and triggerChangeEvent
dropdown_input: added class and styling for hide-placeholder

…roup

Added option "focusOptionOnOpen" to disable auto focus option when dropdown open.
Fixed type of option "searchField"

Added mouseover event listener on dropdown to mark option as active on hover.
Keydown and keyup event set first or last option as active when no option is active.

…ther input field is focused, the autocomplete values popup when the mouse is down on select.

onBlur should only call deactivate when focusInputOnOpen is enabled.

… ist the placeholder input from the dropdown_input plugin

dropdown_input plugin
- add class "placeholder-input" to the placeholder input

virtual_scroll plugin
- added option "clearDropdownBeforeLoadCallback" to the plugin
- if option is set to false, the initial Options won't be removed on loading options from api.

- if the target of document mousedown event ist the placeholder input of the dropdown_input plugin, and the dropdown is open, the event need to be preventDefault, else the dropdown will reopen on mouseup.

Always focus option when search query entered.

…side the wrapper or dropdown.

…ion for optgroup-header

placeholder for search input is set on initialize

- drag_drop plugin: added switching order with arrow keys
- avoid closing the dropdown on drag_drop action
- open the dropdown if the user clicks on a selected option

…s a new option is created

- drag_drop: order of native select should be sorted correctly

…dropdown stays open on drag/drop action

add keydown event for tab to allow closing the dropdown on tab click

…s active

screen reader should announce selected and not selected option in multi select
aria-selected in multiselect should be used for selected options, not active options

…opdown_input is initially focused

added a new setting labelId for referencing

…dingly