Fix bad snapdrop servers and improve stability

[Bastián]

I want to use snapdrop to work and transfer files easily between my devices, but the app only works the 20% of the times that I wanted to use it, please improve the stability of snapdrop web servers in order to be a reliable tool to work with.

[Robin Linus]

If you need a reliable server to work with you should host it yourself. We can't guarantee uptime for the free version.