featurep! will be renamed modulep! in the future, so it's been
deprecated. They have identical interfaces, and can be replaced without
issue.
featurep! was never quite the right name for this macro. It implied that
it had some connection to featurep, which it doesn't (only that it was
similar in purpose; still, Doom modules are not features). To undo such
implications and be consistent with its namespace (and since we're
heading into a storm of breaking changes with the v3 release anyway),
now was the best opportunity to begin the transition.
This is second of three big naming convention changes. In this commit,
we change the naming conventions for hook functions and variable
functions:
1. Replace the bar | to indicate a hook function with a -h suffix, e.g.
doom|init-ui -> doom-init-ui-h
doom|run-local-var-hooks -> doom-run-local-var-hooks-h
2. And add a -fn suffix for functions meant to be set on variables,
e.g.
(setq magit-display-buffer-function #'+magit-display-buffer-fn)
See ccf327f8 for the reasoning behind these changes.
