Range indicator added to placement indicator

New things:

- When building a turret, now you can see its range before you actually place it, so you can better plan ahead!

- Some more improvements on the first new level, Old Outpost.

Bugfixes:

- Missiles now properly got destroyed and when the last enemy dies before a missle hit it, it will actually fly toward the last target and explodes.

- Cyclops5000 fixed. Now it properly hit by missiles.

- New messages do not disable the UI anymore.