命令行光标移动快捷键

切换键主要是Ctrl，少量的Meta（Alt）。

基本移动：

Move back one character. Ctrl + b
Move forward one character. Ctrl + f
Delete current character. Ctrl + d
Delete previous character. Backspace
Undo. Ctrl + -

快速移动：
Move to the start of line. Ctrl + a
Move to the end of line. Ctrl + e
Move forward a word. Meta + f (a word contains alphabets and digits, no symbols)
Move backward a word. Meta + b
Clear the screen. Ctrl + l