Add Eco keymap, factor Crkbd keymap to community layout, other minor tweaks
* Remove outdated Crkbd Ctrl key positioning info
* Add Left Alt key to Lily58 keymap
* Lily58 no longer overrides default TAPPING_TERM
* Refactor Crkbd keymap to use new community layout
* Fix underglow animations for Crkbd w/ Split Common
* Add initial Eco keymap
* Update outdated reference to Crkbd layout
* Add keymap links to userspace readme
* Add copyright notices to files changed in this PR
* Remove more mouse keys settings missed in #8836
* Turn off more unwanted make options
* clang-format my userspace
* Reword ergo layout docs so Crkbd is canonical
* Add a basic readme to my userspace
* Tweak Crkbd readme wording and fix typos
* Enable SPLIT_USB_DETECT for Lily58 w/ Elite-C bug