[Keyboard] New Keyboard: Exent (#6985)

* initial commit

* thank you mr keebs for making this easy. Added 65_ansi macro made from mrkeebs kle2qmk tool.

* split backspace requires an additional row

* change k43 to k42

* add in split space bar support for LAYOUT_all

* add QMK Configurator support

* make default keymap more usable

* update readme

* Update keyboards/exent/info.json

Co-Authored-By: noroadsleft <18669334+noroadsleft@users.noreply.github.com>

* Update keyboards/exent/keymaps/default/keymap.c

Co-Authored-By: fauxpark <fauxpark@gmail.com>

* Update keyboards/exent/keymaps/default/keymap.c

Co-Authored-By: fauxpark <fauxpark@gmail.com>

* Update keyboards/exent/rules.mk

Co-Authored-By: noroadsleft <18669334+noroadsleft@users.noreply.github.com>

keyboards/exent/rules.mk

@@ -0,0 +1,28 @@
+# MCU name
+MCU = atmega32a
+
+# Bootloader selection
+#   Teensy       halfkay
+#   Pro Micro    caterina
+#   Atmel DFU    atmel-dfu
+#   LUFA DFU     lufa-dfu
+#   QMK DFU      qmk-dfu
+#   ATmega32A    bootloadHID
+#   ATmega328P   USBasp
+BOOTLOADER = bootloadHID
+
+# build options
+BOOTMAGIC_ENABLE = no
+MOUSEKEY_ENABLE = no
+EXTRAKEY_ENABLE = yes
+CONSOLE_ENABLE = yes
+COMMAND_ENABLE = yes
+BACKLIGHT_ENABLE = no
+RGBLIGHT_ENABLE = yes
+RGBLIGHT_CUSTOM_DRIVER = yes
+
+OPT_DEFS = -DDEBUG_LEVEL=0
+
+SRC += i2c_master.c
+
+LAYOUTS = 65_ansi 65_iso