Patch the apropos button types so they call helpful instead of the
built-in describe functions. Also add some bindings to apropos-mode-map
so it behaves like other help modes.
Add `doom/describe-symbol` function, which shows documentation for
callable and variable symbols. If a symbol is both a variable and a
callable, it dispatches to apropos. This gives a better workflow than
`helpful-symbol`, which annoyingly prompts the user.
Remap `describe-symbol` to `doom/describe-symbol`, and update
`+emacs-lisp-lookup-documentation` to call it also.
7b4afa32e4