[idea] common shortcut keys

Shortcut key

• Alt+ mouse ： Select multiple columns
• Alt+Insert：getter、setter、 Structure, etc
• Alt+Insert： Click on “Override Methods”, You can choose the method to rewrite
• Ctrl+F9： When only the front-end code is changed , Can be used to refresh , It can be used after the browser is refreshed without restarting
• sout： Output
• Ctrl+D： Paste entire line
• Ctrl+Alt+L ： Automatic typesetting