Running Speed uses longitude angle instead of distance

[qthequartermasterman]

Describe the bug
The running speed of a tank should use the distance from one point to another instead of the angular separation. I believe this is easy to fix by multiplying the change by the radius of the planet.

To Reproduce
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1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior
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Screenshots
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Desktop (please complete the following information):

• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context
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