Fix oversights in plist library
Fix oversights in plist library

- doplist! now returns the RETVAL expression
- Fix doom-plist-merge (was incomplete)

hlissner/doom-emacs,hlissner/.emacs.d,hlissner/.emacs.d,hlissner/doom-emacs,hlissner/.emacs.d,hlissner/.emacs.d,UndeadKernel/emacs_doom,hlissner/doom-emacs,UndeadKernel/emacs_doom,hlissner/doom-emacs,hlissner/doom-emacs,hlissner/.emacs.d,UndeadKernel/emacs_doom,UndeadKernel/emacs_doom,hlissner/.emacs.d,hlissner/doom-emacs,hlissner/.emacs.d,UndeadKernel/emacs_doom,UndeadKernel/emacs_doom,hlissner/.emacs.d,hlissner/doom-emacs,UndeadKernel/emacs_doom