cleaning up headers in skills framework

source/RobotAPI/libraries/skills/core/CMakeLists.txt

source/RobotAPI/libraries/skills/core/ProviderID.h

source/RobotAPI/libraries/skills/core/ProviderInfo.h

source/RobotAPI/libraries/skills/core/Skill.cpp

source/RobotAPI/libraries/skills/core/Skill.h

source/RobotAPI/libraries/skills/core/SkillDescription.cpp

source/RobotAPI/libraries/skills/core/SkillDescription.h

source/RobotAPI/libraries/skills/core/SkillExecutionID.cpp

source/RobotAPI/libraries/skills/core/SkillExecutionID.h

...ce/RobotAPI/libraries/skills/core/SkillExecutionRequest.h

source/RobotAPI/libraries/skills/core/SkillID.cpp

source/RobotAPI/libraries/skills/core/SkillID.h

.../RobotAPI/libraries/skills/core/SkillParameterization.cpp

...ce/RobotAPI/libraries/skills/core/SkillParameterization.h

.../RobotAPI/libraries/skills/core/SkillPreparationInput.cpp

...ce/RobotAPI/libraries/skills/core/SkillPreparationInput.h

source/RobotAPI/libraries/skills/core/SkillStatusUpdate.cpp

source/RobotAPI/libraries/skills/core/SkillStatusUpdate.h

source/RobotAPI/libraries/skills/core/error/Exception.cpp

source/RobotAPI/libraries/skills/core/error/Exception.h