sample.yml: add comments for catalogfile
sample.yml: add comments for catalogfile

kmuto/review,suzuki/review,orangain/review,masawada/review,kmuto/review,kuad9/review_study,krororo/review,murashitas/review,orangain/review,suzuki/review,murashitas/review,kmuto/review,krororo/review,masawada/review,takahashim/review,kuad9/review_study,krororo/review,takahashim/review