Minor tweaks to flygoblin.

elements/flyeye.go

@@ -161,3 +161,7 @@ func (f *FlyEye) ExplosionInitiated() bool {
 func (f *FlyEye) SetExplosionInitiated() {
 	f.sploding = true
 }
+
+func (f *FlyEye) Health() int {
+	return 0
+}