Clarify and fix Radar and Helms Tutorial text

[parracodea]

This pull request updates 3 parts of the tutorial:

Improve Radar Tutorial - Asteroid Section

• Use a larger asteroid, closer to the size players will encounter in a game.
• No longer describe the asteroid as "to the right of your ship" when it is in front of your ship.
• Clarify tutorial text.

Radar Tutorial: Correctly describe Station icons

Helms Tutorial: Clarify language

The text references Beam Weapons, something that the player has not yet encountered if only playing the Helm Tutorial.