zpanel upgrade script

[Me.B]

Main changes from zpanel to sentora:

1. DB name's changed from zpanel_* to sentora_*
2. Path change from /etc/zpanel to /etc/sentora and /var/zpanel to /var/sentora
3. Added separate db user for FTP/Roundcube/Postfix, no more use root, only panel use root.
4. Panel code upgraded. Adviced better to drop extra plugins.
5. Config files tuning for FTP/DNS/Mail to use the new users.
6. DB update files for some postfix files and roundcube.
7. Database content: (specially x_settings) and translations:

• each term "ZPanel" or "Zpanel" or "ZPanel" or "zPanel" is replaced by "Sentora"
  
  
• each term "zpanel" (all lower case) is replaced by "sentora" (lower case too)
  

This is a quick summary of main changes I remember we made over zpanel > sentora 1.0.

M B