`d` without arguments should redirect to home directory

[mmagician]

IDK if it's just my current shell or whether the behaviour has changed, but previously just d by itself would take me to the home directory, whereas now it complains that argument is required. Certainly from my perspective it would be more intuitive to have d mimic cd, which would return to home.

[mmagician]

Also I can't tag home even if I wanted to:

> tag ~ home
Nothing to do