Jonathan Vanherpe

Fix bug that caused plugin to stop working in php 5.6

1

I was running into [this issue too](https://wordpress.org/support/topic/wordpress-backup-to-dropbox-wpb2d-), and didn't feel like downgrading my php version. All of this code is borrowed from https://github.com/xgin/Dropbox/commit/1978b382f335df71a414b34eb81e0da198fd4157 It seems to work in my tests,...