Merge pull request #114 from KazumaKobayashi/develop

バグ修正
Merge pull request #116 from KazumaKobayashi/develop

add logger and small refactor. fixed #113 #112
Merge pull request #117 from KazumaKobayashi/develop

add max length. fixed #109
Add flag
Add Flag part2
Add DisplayFlag
A few Change
change flag method
Merge pull request #119 from KazumaKobayashi/master

位置の表示非表示フラグの追加