handwired/space_oddity: refactor, Configurator support and readme cleanup (#4977)

* handwired/space_oddity: refactor

- config.h: updated to use #pragma once include guard
- rules.mk: replace `?=` with `=`
- space_oddity.h:
  - updated to use #pragma once include guard
  - layout macro KEYMAP renamed to LAYOUT
- default keymap:
  - updated to use #include QMK_KEYBOARD_H
  - replace references to Planck keycodes
  - replace fn_actions-powered layer switch keycode
  - rebuild keymap block comments
  - keymap layers now use short-form keycodes
  - refactor action_get_macro keycodes into process_record_user

* handwired/space_oddity: Configurator support

* handwired/space_oddity: readme cleanup

- update readme to better conform with QMK template
- fixed the make command.

keyboards/handwired/space_oddity/readme.md

@@ -1,5 +1,6 @@
-Space Oddity Keyboard
-=====================
+# Space Oddity Keyboard
+
+![Space Oddity](https://i.imgur.com/dE9Y4XK.jpg)
 
 This firmware is for an Emacs-focused handwired custom keyboard using an Arduino Pro Micro.
 
@@ -7,7 +8,10 @@ As originally designed, the top row consists of 2u keys which are used for user-
 
 Some simple example macros are included. To add your own, just add the number of the macro you want in the appropriate section.
 
-A picture of the finished product can be found here: https://imgur.com/dE9Y4XK
+This design was conceived by James Taylor. Any requests for further information, suggestions, and/or tips for building your own are welcome!
+
+Keyboard Maintainer: [James Taylor](https://github.com/broken-username)  
+Hardware Supported: Arduino Pro Micro  
 
 ## Pinout
 
@@ -15,11 +19,16 @@ The following pins are used:
 - Columns 1-12: B2, B6, B5, B4, E6, D7, C6, D4, D0, D1, D2, D3
 - Rows 1-6: F4, F5, F6, F7, B1, B3
 
-## Compiling and loading the firmware
+## Flashing
 
-To build the firmware, run `make handwired/space_oddity` from the toplevel directory.
+Make example for this keyboard (after setting up your build environment):
 
-On GNU/Linux, you can flash the default layout onto the microcontroller by using `avrdude -p atmega32u4 -P /dev/ttyACM0 -c avr109 -U flash:w:handwired_space_oddity_default.hex`. Note that the device name under `/dev` may be different. 
+    make handwired/space_oddity:default
 
+On GNU/Linux, you can flash the default layout onto the microcontroller by using
 
-This design was conceived by James Taylor. Any requests for further information, suggestions, and/or tips for building your own are welcome!
+    avrdude -p atmega32u4 -P /dev/ttyACM0 -c avr109 -U flash:w:handwired_space_oddity_default.hex
+    
+Note that the device name under `/dev` may be different. 
+
+See the [build environment setup](https://docs.qmk.fm/#/getting_started_build_tools) and the [make instructions](https://docs.qmk.fm/#/getting_started_make_guide) for more information. Brand new to QMK? Start with our [Complete Newbs Guide](https://docs.qmk.fm/#/newbs).