Switch to libossp-uuid, to get UUIDs on Windows

This was only used to avoid a necessary check in collab builds on
Windows. @jtanx, who does the Windows binaries, says collab currently
isn’t building on Windows anyway.
On 26 October 2014 06:05, monkeyiq <notifications@github.com> wrote:

> It will cause a FontForge version break as of when you merged the code
> because the username and machinename fields will have moved 7 bytes back
> now in a beacon_announce_t message. So all fontforges before yesterday will
> be able to read each other's beacons, and all fontforges today onwards will
> work with each other, but those two sets of builds will not be happy with
> each other's beacons.



That is good, it gives us a reason to go to 2.1.0 for the next release,
according to semver.org principles :)