Fixed typos

Signed-off-by: Stefan Marr <git@stefan-marr.de>
Fixed some whitespace

Signed-off-by: Stefan Marr <git@stefan-marr.de>
Fixed typo

Signed-off-by: Stefan Marr <git@stefan-marr.de>
Subprocess timeout rewritten to use threads

This change is necessary to enable threaded execution, because signals can only be handled by the main thread.

Signed-off-by: Stefan Marr <git@stefan-marr.de>