Fixes #6647

grabbed_by assignment is now done in the grab constructor, instead of
leaking out all over the place.
Less relative paths. Less type checks.
Fixes #6648

Adds missing list-reference.
Fixes runtime caused by missing check in sleeper code
Fixes shuttle control NanoUI issue

Should again be possible to initialize the early shuttle launch.
Merge pull request #6650 from mwerezak/grab

Fixes #6647
Merge pull request #6654 from PsiOmegaDelta/Shuttle

Fixes shuttle control NanoUI issue
Merge pull request #6653 from GinjaNinja32/sleeper

Fixes runtime caused by missing check in sleeper code
Merge pull request #6652 from PsiOmegaDelta/Centcom

Fixes #6648