require libuuid

- require libuuid at build time and remove insufficiently seeded
  replacement for uuid()

src/util.h

@@ -34,9 +34,7 @@
 #include <sys/types.h>
 #include <Task.h>
 
-#ifdef HAVE_UUID
 #include <uuid/uuid.h>
-#endif
 
 // util.cpp
 bool confirm (const std::string&);
@@ -46,7 +44,7 @@ void delay (float);
 std::string formatBytes (size_t);
 int autoComplete (const std::string&, const std::vector<std::string>&, std::vector<std::string>&, int minimum = 1);
 
-#if defined(HAVE_UUID) && !defined(HAVE_UUID_UNPARSE_LOWER)
+#ifndef HAVE_UUID_UNPARSE_LOWER
 void uuid_unparse_lower (uuid_t uu, char *out);
 #endif
 const std::string uuid ();