Update `npm` as well

It no longer conflicts with Homebrew (homebrew/homebrew#27479).

This reverts commit 5a70ba8219867d86c1c2c80d91fead4dd457036c.
Update submodules
Don’t use global aliases
Shorten `git update-submodules` and `empty dsstore`
+ bin/git-l

+ bin/git-ll