内容
変更前
{ "keys": ["alt+shift+up"], "command": "select_lines", "args": {"forward": false} },
{ "keys": ["alt+shift+down"], "command": "select_lines", "args": {"forward": true} },
変更後
{ "keys": ["ctrl+alt+pageup"], "command": "select_lines", "args": {"forward": false} },
{ "keys": ["ctrl+alt+pagedown"], "command": "select_lines", "args": {"forward": true} },
