Accessibility: aria-support for p-autocomplete advanced

[moma1806]

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Current behavior
Screenrader jaws can not identify the p-autocomplete as select element. It only identifies an input.

Expected behavior
When focussing a p-autocomplete, the screenreader should describe it as a select field and offer the posibility to reach the options list.
This can be achieved using ARIA-roles
https://www.w3.org/WAI/PF/aria/roles#role_definitions
role=listbox for the focussing input element
role=button and aria-label="..." for the opening button
role=option for the dropdown-elements

Minimal reproduction of the problem with instructions
Using jaws17 combined with IE11 on demo page and tabbing until
https://www.primefaces.org/primeng/#/autocomplete

What is the motivation / use case for changing the behavior?
The accessibility of an important form element for screenreader.

Please tell us about your environment:
Windows 10, Eclipse Oxygen 4.7

• Angular version: 5.X
  version: 5.1.0
• PrimeNG version: 5.X
  version: 5.2.0
• Browser: [all | Chrome XX | Firefox XX | IE XX | Safari XX | Mobile Chrome XX | Android X.X Web Browser | iOS XX Safari | iOS XX UIWebView | iOS XX WKWebView ]

• Language: [all | TypeScript X.X | ES6/7 | ES5]

• Node (for AoT issues): node --version =
  version: 7.5.0