Php7 android7 sync issue (#222)

* Casting result of column sms_mailbox to int in db sanitize check.

* Added mailbox id 3 to the list of sms messages to select (This should be Mailbox "All", but it seems, on AOSP v7.1 - Nougat - the messages could be stored there instead of 1 or 2).

* Extended all sms_mailbox parameters, to include mailbox number 3.
It's not so much a sync than rather a display issue.

* Fixed a wrong value in the database query parameters.