[Keymap] Planck Keymap :: rjhiglefort (#5059)

* copy default over as starting point

* Getting rid of dvorak and colemak for now, added a couple changes to the
keymap

* removed refs to bad layers, formatting comments

* First version of my ergodox ported layout!

* Symbols layer, media layer, updated comments

* Hyper as a single key

* Fix stuck hyper key when switching layers

* Tweak some annoying things about the layout.

- move raise left and promote alt
- remove swap keys on the last layer
- reorganize media keys so they're easier to reach and more intuitive
- fix some comment template things

* Add readme for rjhilgefort planck layout

* readme tweak

* PR feedback changes