armarx_integration/robots/armar6/skills: Require Spoac explicitly
!637 (merged) removes Spoac as requirement of SpeechX. For ARMAR-6, we want to keep it, so I added it to the module for armar6_skills.
!637 (merged) removes Spoac as requirement of SpeechX. For ARMAR-6, we want to keep it, so I added it to the module for armar6_skills.