Revert "仅使用 pid 防止重复运行可能会发生碰撞，因此还使用 argv[1]"

This reverts commit 1a35d7be7bf695fd5ab6b3133ba594b5677282e1.

Conflicts:
	src/LoginInfo.py
Revert "运行脚本向 argv[1] 传递一个魔法字符串"

This reverts commit caf065430675fc44c3f0d9310fde26792919a7a9.
Safer split().
AsyncFetcher: Code cleanup.
AsyncFetcher: add logging and a comment.
Using WECASELOG env to set the log level.
Ignore case.
Fix an error.
Remove current account from LoginInfo after logout.
LoginInfo: Major rewrite.