CON-1709 | contribute button + dropdown

I don't know if I follow you right, but the 'text' and 'href' cases are special. There can be more link attributes like 'accesskey', 'data-content' and 'class'. Do you still think that it would be more optimal solution to hard code all of the known possibilities than implement a loop?
```php
// one of $dropdownItems items
    'wikiactivity' =>
        [
            'text' => 'Wiki aktywność'
            'data-content' => 'Wiki aktywność'
            'href' => '/wiki/Special:WikiActivity'
            'accesskey' => 'g'
        ]
```
Above goes to:
```php
// one of $dropdownItemsRender items
    'wikiactivity' =>
        [
            'attributes' => ' data-id="wikiactivity" data-content="Wiki aktywność" href="/wiki/Special:WikiActivity" accesskey="g"'
            'text' => 'Wiki aktywność'
        ]
```
which can be used easily in the template.

P.S. I changed the code to make it more obvious what is going on in there.