Update .gitignore for developers using QtCreator
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Remove obsolete/undocummented command line switches

Spotted undocummented/obsolete switches '-s' and '-f' equivalent to
'start' and 'stop' respectively. Removing for convenience.

Change-Id: I17f46dbd0a18ef6669c3b9c8372845bab635d172
main.cc: Fix obsolete if-condition double check