Added 20 sets to [DGC] Collection

Previews & DDL:

	[DGC] 2008.12 No.661 Azusa Itagaki 板垣あずさ
	[DGC] 2008.12 No.662 Saori Shiina 椎名沙織
	[DGC] 2008.12 No.663 Rina Sasamoto 笹本りな
	[DGC] 2008.12 No.664 Noriko Kijima 木嶋のりこ
	[DGC] 2008.12 No.665 Yuna Mizusawa 水沢優那
	[DGC] 2008.12 No.666 Tsubasa Nagumo 南雲つばさ
	[DGC] 2009.01 No.667 Aki Hoshino ほしのあき
	[DGC] 2009.01 No.668 Mika Inagaki 稲垣実花
	[DGC] 2009.01 No.669 Mikie Hara 原幹恵
	[DGC] 2009.01 No.670 Meguru Ishii 石井めぐる
	[DGC] 2009.01 No.671 Akiho Yoshizawa 吉沢明歩
	[DGC] 2009.01 No.672 Yui Tatsumi 辰巳ゆい
	[DGC] 2009.01 No.673 Mayu Kanaoka 叶丘真悠
	[DGC] 2009.01 No.674 Chie Amemiya 雨宮チエ
	[DGC] 2009.01 No.675 Haruka Nagase 永瀬はるか
	[DGC] 2009.01 No.676 Mai Mizuta 水田麻依
	[DGC] 2009.01 No.677 Reona Kurosaki 黒崎れおな
	[DGC] 2009.02 No.678 Miu Nakamura 仲村みう
	[DGC] 2009.02 No.679 Miu Nakamura 仲村みう
	[DGC] 2009.02 No.680 Azusa Yamamoto 山本梓