job运行模式介绍

终端直接执行 datax.py 时，输出如下内容：
-m , --mode=
Set job runtime mode such as: standalone, local,
distribute. Default mode is standalone.
这里的 job 模式有没有文档能够介绍下？

Start by running datax.py with the help output shown in the issue and inspect how the standalone, local, and distribute modes are described or selected. Done means adding documentation that explains each job runtime mode, its use case, and the standalone default.

Written by the indexing model from the issue text.