[Keymap] Add Endemoniada keymaps (#6875)

* Add dz60 keymap

* Add my TADA68 layout

* Fix descriptions and formatting

* Formatting fixes

* Add readme file

* Formatting

* move caps lock to correct key, add F-keys to both layers

* Add readme for dz60

* First draft of custom Let's Split layout

* Some more keys

* Finalized keymap

* Added a bunch of custom shortcuts to make layout easier to read

* Add PERMISSIVE_HOLD option to modtap behavior

* Add lock and sleep shortcuts, formatting

* Minor fixes and adjustments

* Add PERMISSIVE_HOLD option, add sleep/lock shortcuts, minor fixes

* Add sleep/lock shortcuts, minor fixes

* fixups

* Major simplification of lets_split layout into more standard raise/lower/special layers

* Remove layer songs, add to readme

* Formatting

* Switch a few keys around for reachability

* Add windows/mac specific layers

* simplify layers

* Update README

* Fix legends

* Invert numpad and put Del in upper right corner

* Disable arrow keys on Raise, add build instructions

* Move dz60 keymap to its own branch

* Remove redundant configuration

* Change volume and sleep keycodes to standard

* Removing empty rules.mk

* Changing layer defines to enum

* Adding comment to explain reason for swapping KC_TRNS and KC_NO fillers

1 files changed, 65 insertions, 0 deletions

diff --git a/keyboards/lets_split/keymaps/mekberg/README.md b/keyboards/lets_split/keymaps/mekberg/README.md
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+# Let's Mekberg!
+
+This is my take on a Swedish 40% layout in a split format. The priority is to have the most highly used keys opposite the modifier to make chording simpler. In other words, if the layer modifier is on the left half, the most used keys should be bound on the right half.
+
+## Layers
+
+### Default
+
+The default layer has normal alpha layout with the addition of Swedish letters, causing Enter to move down one key and backspace to take the place of the right space. The enter key also doubles as Shift when held.
+
+2nd row left modifier has been bound to both Ctrl and Tab with modtap (hold for Ctrl, tap for Tab).
+
+Delete is available on all non-default layers, positioned on the upper right corner key.
+
+### Raise
+
+The raised layer has all the symbols and special characters predefined. As much as possible, there should be no need to use additional modifiers.
+
+Arrow keys have been disabled on this layer to avoid accidental misclicks when pressing the Raise key.
+
+#### macOS / Windows variants
+
+Because macOS and Windows expect quite different keycodes to produce the same special characters (for example '{' or  '|'), there are two different layers, one for each OS. To toggle either macOS (default) and Windows layouts within the RAISE layer, press SPECIAL + W for Windows or SPECIAL + M for macOS.
+
+### Lower
+
+The lower layer focuses on numbers, with a numpad-like layout on the right and F-keys in a homerow-centric layout on the left.
+
+### Special
+
+The special layer has Reset and EEP Reset keys on the left half, along with media and volume controls. On the right half it has movement keys starting in the IJKL cluster. Additionally, custom macOS Sleep and Lock Screen keys can be found on the right half on this layer.
+
+## Configuration
+
+### PERMISSIVE_HOLD
+
+This option is used because otherwise modtap functions would fail to trigger. This increases reliability for me.
+
+### USE_SERIAL
+
+N/A
+
+### EE_HANDS
+
+Prepared for EEPROM settings and different keymaps depending on USB port connected, but default master side remains left regardless.
+
+## Building
+
+Clean the build environment:
+
+```shell
+make clean
+```
+
+Build and flash left side:
+
+```shell
+make lets_split/rev2:mekberg:avrdude-split-left
+```
+
+Then do the same for the right side:
+
+```shell
+make lets_split/rev2:mekberg:avrdude-split-right
+```