Update to v1.5.6.0

After a long time of no updates, here comes the latest version of DropboxPortableAHK.
I put this together very quickly to address the current issues regarding the automatic Dropbox update to v1.6.18 and v2.0.0, a further update will arrive during the next days.

Also, I want to thank you all for your support, your donations and thank-you emails and comments are highly appreciated and bring a smile to my face every time I get a new one. They remind me of why I keep supporting DropboxPortableAHK and that there are still so many people out there who use it on a regular basis. Thank you, guys, you rock!