いろんなフォントで「open_letter」変換
Zen Old Minchoopen_letter
Yusei Magicopen_letter
M PLUS 1open_letter
Shippori Antiqueopen_letter
Yuji Maiopen_letter
Dela Gothic Oneopen_letter
DotGothic16open_letter
Train Oneopen_letter
Hira Minchoopen_letter
Potta Oneopen_letter
Reggae Oneopen_letter
Stickopen_letter
Zen Kurenaidoopen_letter
Kosugi Maruopen_letter
Rampart Oneopen_letter
Hachi Maru Popopen_letter
New Tegominopen_letter
RocknRoll Oneopen_letter
Kaisei Decolopen_letter
「open_letter」をコピペできる装飾文字に変換（旧字体・丸囲みなど）
