fix "error 1014" on site-alias::del() request
 Merge branch 'fix_site-alias_del_issue' into 'master'

Fix Site Alias Del Issue

фикс ошибки запроса на удаление алиаса сайта

на запрос удаления алиаса

**2014-02-22 09:46:12 REQUEST site-alias => del**

```xml
<?xml version="1.0" encoding="UTF-8"?>
<packet version="1.6.3.1">
    <site-alias>
        <del>
            <filter>
                <name>ekkl.ru.plsk.regruhosting.ru</name>
            </filter>
        </del>
    </site-alias>
</packet>
```
at `/usr/local/lib/perl5/site_perl/5.14.2/API/Plesk.pm` line 78.

приходит ответ плеска

**2014-02-22 09:46:12 RESPONSE site-alias => del**

```xml
<?xml version="1.0" encoding="UTF-8"?>
<packet version="1.6.3.1">
    <system>
        <status>error</status>
        <errcode>1014</errcode>
        <errtext>Parser error: Request is invalid. Error in line 1: Element 'del': This element is not expected. Expected is one of ( create, get, set, delete, rename, get-supported-services ).</errtext>
    </system>
</packet>
```
at `/usr/local/lib/perl5/site_perl/5.14.2/API/Plesk.pm` line 82.