[Keyboard] Add AMJ66 keyboard (#5945)

* Added nearly perfect config for AMJ66, only missing top right key.

* Correct the layout macro

* Add layout mock-up to amj66.h

* Update and comment out the backlight definitions in config.h

The backlight pin was found to be D4, but there appears to be a bug in QMK that affects this keyboard.

Commenting out for now.

* Try to make a sensible default keymap

* Add testing keymap for FSund

Include the keymap that was being used for testing.

Don't forget to refactor this later into an actually useful keymap.

* Suggestions by fauxpark

- uncomment the backlight configuration
- fix the default keymap
- remove commented MCU rule
- specify the bootloader
- make mental note to not try to write code at 3:30 in the morning

* Add LAYOUT_66_ansi and LAYOUT_66_iso macros

- include QMK Configurator data
- enable Community Layout support

* Add comments about layout variants to amj66.h

* Add #define BACKLIGHT_ON_STATE 1

Partial fix for backlight breathing.

- Requires #5983 to fix fully (confirmed by FSund and fauxpark)

Co-Authored-By: fauxpark <fauxpark@gmail.com>
Co-Authored-By: Filip Sund <filip.sund@gmail.com>

* DEBOUNCING_DELAY -> DEBOUNCE

* Move AMJ66 files into new AMJKeyboard directory

* Correct Manufacturer in USB Device Descriptor

* Remove comment regarding source fork

* Correct the readme

* Update default keymap to match the details given in its readme

* White-space edit fsund_test keymap

Makes its formatting more consistent with other 66% keymaps. No logic changes.

* Linting info.json

Debug-style linting (one key object per line) and minor edits to key labels.

* Remove fsund_test keymap

* Add FSund as a maintainer in info.json

1 files changed, 70 insertions, 0 deletions

diff --git a/keyboards/amjkeyboard/amj66/rules.mk b/keyboards/amjkeyboard/amj66/rules.mk
new file mode 100644
index 0000000000..80734a9904
--- /dev/null
+++ b/keyboards/amjkeyboard/amj66/rules.mk
@@ -0,0 +1,70 @@
+# MCU name
+MCU = atmega32u4
+
+# Processor frequency.
+#     This will define a symbol, F_CPU, in all source code files equal to the
+#     processor frequency in Hz. You can then use this symbol in your source code to
+#     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
+#     automatically to create a 32-bit value in your source code.
+#
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
+#     does not *change* the processor frequency - it should merely be updated to
+#     reflect the processor speed set externally so that the code can use accurate
+#     software delays.
+F_CPU = 16000000
+
+
+#
+# LUFA specific
+#
+# Target architecture (see library "Board Types" documentation).
+ARCH = AVR8
+
+# Input clock frequency.
+#     This will define a symbol, F_USB, in all source code files equal to the
+#     input clock frequency (before any prescaling is performed) in Hz. This value may
+#     differ from F_CPU if prescaling is used on the latter, and is required as the
+#     raw input clock is fed directly to the PLL sections of the AVR for high speed
+#     clock generation for the USB and other AVR subsections. Do NOT tack on a 'UL'
+#     at the end, this will be done automatically to create a 32-bit value in your
+#     source code.
+#
+#     If no clock division is performed on the input clock inside the AVR (via the
+#     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
+F_USB = $(F_CPU)
+
+# Interrupt driven control endpoint task(+60)
+OPT_DEFS += -DINTERRUPT_CONTROL_ENDPOINT
+
+
+# Bootloader selection
+#   Teensy       halfkay
+#   Pro Micro    caterina
+#   Atmel DFU    atmel-dfu
+#   LUFA DFU     lufa-dfu
+#   QMK DFU      qmk-dfu
+#   atmega32a    bootloadHID
+BOOTLOADER = atmel-dfu
+
+
+# Build Options
+#   change yes to no to disable
+#
+BOOTMAGIC_ENABLE = lite      # Virtual DIP switch configuration(+1000)
+MOUSEKEY_ENABLE = yes       # Mouse keys(+4700)
+EXTRAKEY_ENABLE = yes       # Audio control and System control(+450)
+CONSOLE_ENABLE = yes        # Console for debug(+400)
+COMMAND_ENABLE = yes        # Commands for debug and configuration
+# Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
+SLEEP_LED_ENABLE = no       # Breathing sleep LED during USB suspend
+# if this doesn't work, see here: https://github.com/tmk/tmk_keyboard/wiki/FAQ#nkro-doesnt-work
+NKRO_ENABLE = no            # USB Nkey Rollover
+BACKLIGHT_ENABLE = yes      # Enable keyboard backlight functionality on B7 by default
+MIDI_ENABLE = no            # MIDI support (+2400 to 4200, depending on config)
+UNICODE_ENABLE = no         # Unicode
+BLUETOOTH_ENABLE = no       # Enable Bluetooth with the Adafruit EZ-Key HID
+AUDIO_ENABLE = no           # Audio output on port C6
+FAUXCLICKY_ENABLE = no      # Use buzzer to emulate clicky switches
+
+LAYOUTS = 66_ansi 66_iso