Description

Some dropdown fixes:
a) multiple and maxselections allowed more than the limit to be selected when labels are used
b) uselabels:false + saveremotedata:true und preselected values created labels
c) init from select and preselected value including an ampersand wasn't preselected

Testcase

a)

Broken

• Open the dropdown via click on dropdown icon. Although the selection should be limited to 2 entries, you can add more entries
• Clicking inside the dropdown does nothing
  https://jsfiddle.net/lubber/1oeLn7h6/5/

Fixed

• Clicking inside the dropdown as well as opening it from the dropdown icon just shows the "max 2 selected values" as expected
  https://jsfiddle.net/lubber/1oeLn7h6/6/

b)

Broken

The dropdown shows 2 preselected labels, although labels should not be used
https://jsfiddle.net/lubber/c8eub9fo/2/

Fixed

"2 selected" shown as expected
https://jsfiddle.net/lubber/c8eub9fo/3/

c)

Broken

Dropdown made out of a select does not create the preselected labels which contains an ampersand
https://jsfiddle.net/lubber/qykf58tc/3/

Fixed

Preselected as expected
https://jsfiddle.net/lubber/qykf58tc/2/

Closes

#2782