Added undefined behavior sanitizer.

Combined common sanitizer flags.
Added fuzzers.

fuzzing/fuzz-LeaseSet.cc

@@ -0,0 +1,21 @@
+
+
+#include <stdint.h>
+#include <stddef.h>
+
+#include <LeaseSet.h>
+
+#include "fuzzing.h"
+
+
+bool
+fuzzing_testinput(const uint8_t * data, size_t size)
+{
+	i2p::data::LeaseSet * ls;
+
+
+	ls = new i2p::data::LeaseSet(data, size, false);
+	delete ls;
+
+	return true;
+}