Flycheck will now wait longer to check for errors when the last check
produced no errors, and quicker when there are. It will also avoid
displaying flycheck-posframe if in insert mode (as it can disturb cursor
positioning and change evil state in some edge cases).
+ Add doom-switch-frame-hook
+ Replace doom-{enter,exit}-{buffer,window}-hook with
doom-switch-{buffer,window}-hook
+ New switch-buffer hooks run on buffer-list-update-hook rather than
in select-window advice.
+ Blank our buffer-list-update-hook in some places to reduce how many
times it gets triggered.