[ja] Apply 1f57d57a48144a978d9f8b52c38550804297ee1d
[ja] Apply 0c34253095f327209aceab8b3170f93b0c0c4ed9
[ja] Apply 7d11ee56e37975c33cc0646d72cb818db4d10666
[ja] Apply 7ba488683f86e8b507c0f04c36544f512bbc3447
[ja] Apply cfdce8587ed1654f07665660d5347a4b6309a062
[ja] Apply b294744d98a6f6cdbc3508b0058f8616147c1596
[ja] Apply c3ae214db985a4971509942bb8df121653ccf8ae
[ja] Apply 4f7c71dd6fe818d8e56e62565f9dfedb444e1ce1
[ja] Apply 5502e94d3237d285eb3157cc7e4d6710d650464e
[ja] Apply df7639bb6d5b6ef453de18bd43d0b7f59464d1ab
[ja] Apply 716e1926c63890027cf133492bf59c8f05e8bfa1
[ja] Apply a7159aead8a1ec9a8734df57a6d850d43a423089
[ja] Apply aa830655d85f8799554a8789a9607347c81e47be
Merge pull request #450 from harupong/ja-chapter2

[ja]Update chapter2
Merge branch 'progit/master'