Improve: move UserVoiceComponent::css and UserVoiceComponent::javascript to UserVoiceComponent::settings

DebugKitと異なりcssとjavascriptを変更したい場合に備えて、
UserVoiceComponentのオプションに移動した
Merge pull request #3 from k1LoW/move_to_settigs

Improve: move UserVoiceComponent::css and UserVoiceComponent::javascript to UserVoiceComponent::settings