Update elfinder.vi.js

Translate error messages
Update elFinder.class.php

spelling correction
VolumeDriver archivers : undefined create index

Somehow on my integration environment the archivers array is empty and causes an undefined index. (probably some extension being deactivated)
Merge pull request #867 from sherbrow/patch-1

VolumeDriver archivers : undefined create index
Merge pull request #863 from dyonenedi/patch-1

Update elFinder.class.php
Merge pull request #841 from ngson2000/patch-1

Update elfinder.vi.js
[ui:core] copy icon of dragging icon is changed quickly
Merge branch '2.x' into 2.1
Merge branch '2.1' into 2.1_n