add rb doc for usage with yard
add rb doc for usage with yard

kwketh/otclient,Radseq/otclient,dreamsxin/otclient,gpedro/otclient,dreamsxin/otclient,gpedro/otclient,gpedro/otclient,Cavitt/otclient_mapgen,EvilHero90/otclient,kwketh/otclient,dreamsxin/otclient,Cavitt/otclient_mapgen,EvilHero90/otclient,Radseq/otclient