Added 20 sets to [DGC] Collection

Previews & DDL:

	[DGC] 2010.08 No.861 Ai Shinozaki 篠崎愛
	[DGC] 2010.08 No.862 Ayaka Sayama 佐山彩香
	[DGC] 2010.08 No.863 Haruka Ito 伊東遥
	[DGC] 2010.08 No.864 Mika Kayama 佳山三花
	[DGC] 2010.08 No.865 Ryouko Iori 伊織涼子
	[DGC] 2010.08 No.866 Saya Fujishiro 藤代さや
	[DGC] 2010.08 No.867 Sayaka Mizutani 水谷彩也加
	[DGC] 2010.08 No.868 Momoka Himenoki 姫乃木桃香
	[DGC] 2010.09 No.869 Aya Kiguchi 木口亜矢
	[DGC] 2010.09 No.870 Momoko Tani 谷桃子
	[DGC] 2010.09 No.871 Saki Seto 瀬戸早妃
	[DGC] 2010.09 No.872 Minori Hatsune 初音みのり
	[DGC] 2010.09 No.873 Kaede Fuyutsuki 冬月かえで
	[DGC] 2010.09 No.874 RUMIKA
	[DGC] 2010.09 No.875 Minori Kawahara 河原実乃梨
	[DGC] 2010.09 No.876 Nanako Ijiri 井尻菜々子
	[DGC] 2010.09 No.877 Natsumi Minagawa 皆川なつみ
	[DGC] 2010.10 No.878 Risa Yoshiki 吉木りさ
	[DGC] 2010.10 No.879 Minase Yashiro 八代みなせ
	[DGC] 2010.10 No.880 Mari Sakurai 桜井まり