Switched to use Dropbox v2 API

Implemented to use the Dropbox v2 API as the v1 was dropped.
Start using this PHP SDK: https://github.com/kunalvarma05/dropbox-php-sdk

Fixed to always remove backup files

If there is a problem on backuping all files the backup archive will stay on the server.
That could lead to quick disk spaces exhausting.
Fix is to always remove the backup.
We found out that when you backup full cPanel home folder sometimes there are lock files
that are changed or not be able to read them and tar produce error/warning messages.
That leaded to not deleting the backup after uploading it.

Changed to add Year-Month to destination backup sub directory

This change is usefull to make nice ordered directories for the backups.

Separate Dropbox SDK PHP directory

Several other fixes as well.

Config Options Fixes

Fix to have single config option section in the beginning of the script.

Last Minute Fixes

What changed:

• Use the latest Dropbox PHP SDK v1.1.6
• Separate config options to required and default ones to minimize config file content.

First official version!

Initial first official version!!

Happy backups to all of you!!!

This version includes Dropbox PHP SDK v1.1.5