Documentation fixes from upstream

[MoralCode]

There are a few documentation issues from the upstream repo (https://github.com/kubos/kubos) that should be fixed. Many of them should be pretty easy fixes

heres a mostly-complete list of the most recent ones:

• Documentation for Local Development should not use system Python kubos/kubos#552
• Update Documentation to specify rust version 1.39.0 where needed kubos/kubos#553
• Documentation for passing additional arguments for app service is wrong kubos/kubos#555
• Verify docs front page links kubos/kubos#542

These ones may require a little more work and may be borderline as far as good-first-issues are concerned:

• Contributors guide is missing some information kubos/kubos#513
• Docs for killing an app still have run levels kubos/kubos#527
• Verify that the payload service tutorial is still accurate kubos/kubos#529