Change ftp_scan_dir from 'private' to 'protected' to add ability to reimplement it.
Change http request in 'open' command from GET to POST to hide url custom parameters (like passwords)
Run archivators via 'proc_open' instead of 'exec' because it works well on MS IIS
Invalid permissions on TMP directory
New driver to work with IIS FTP
[core:resources] filename text selects with out extention on file copy
[VolumeDriver] new func `getArchivers` for calls from `_checkArchivers`

Added new function `getArchivers()` for calls from `_checkArchivers()`.

`getArchivers()` catching exists archivers into session data for improve
performance.

ex.
```php
protected function _checkArchivers() {
	$this->archivers = $this->getArchivers();
	return;
}
```

And, added cmd check about `7z` for windows server.

ref. #550, #722
Merge branch '2.x' into 2.1
Merge pull request #673 from mailtoartem/2.x

Change ftp_scan_dir from 'private' to 'protected' to add ability to reim...
Merge branch '2.x' into 2.1
fix error with empty folder uploading on Google Chrome
fix problem of DnD, clipboard uploading with Google Chrome
Copy & Paste in same Folder Fix

#739
Merge branch '2.x' into 2.1
enable dblClick on fileSelector(div) in icon view
[ui,cwd] fix hover of cwd
Merge branch '2.x' into 2.1
[css.cwd] add "border:none;" into .elfinder-cwd-file
Merge branch '2.x' into 2.1
[core] add 'distance:8' into fm.draggable object

For prevent unwanted drags when (dbl)clicking.