Add an easy way to create new keymaps for your favorite keyboard (#3868)

* initial commit of keymap creation script

* create default keymap

* pass shellcheck

* provide a better usage message

* change printf string to more accurately reflect the path

* make it more easily understood

* found another typo

* add documentation regarding the new_keymap script

* enforce lowercase for userinputs

util/new_keymap.sh

@@ -0,0 +1,40 @@
+#!/bin/sh
+# Script to make a new keymap for a keyboard of your choosing
+# This script automates the copying of the default keymap into
+# your own keymap
+
+KB_PATH=$(echo "$1" | tr 'A-Z' 'a-z')
+USERNAME=$(echo "$2" | tr 'A-Z' 'a-z')
+
+if [ -z "$KB_PATH" ]; then
+    printf "Usage:   %s <keyboard_path> <username>\n" "$0"
+    printf "Example: %s 1upkeyboards/1up60hse yourname\n" "$0"
+    exit 1
+fi
+
+if [ -z "$USERNAME" ]; then
+    printf "Usage:   %s <keyboard_path> <username>\n" "$0"
+    printf "Example: %s 1upkeyboards/1up60hse yourname\n" "$0"
+    exit 1
+fi
+
+cd ..
+
+if [ ! -d "keyboards/$KB_PATH" ]; then
+	printf "Error! keyboards/%s does not exist!\n" "$KB_PATH"
+	exit 1
+fi
+
+if [ -d "keyboards/$KB_PATH/keymaps/$USERNAME" ]; then
+	printf "Error! keyboards/%s/keymaps/%s already exists!\n" "$KB_PATH" "$USERNAME"
+	exit 1
+fi
+
+# Recursively copy the chosen keyboard's default keymap
+cp -r keyboards/"$KB_PATH"/keymaps/default keyboards/"$KB_PATH"/keymaps/"$USERNAME"
+
+printf "%s keymap directory created in: qmk_firmware/keyboards/%s/keymaps/\n\n" "$USERNAME" "$KB_PATH"
+
+printf "Compile a firmware file with your new keymap by typing: \n"
+printf "   make %s:%s\n" "$KB_PATH" "$USERNAME"
+printf "from the qmk_firmware directory\n"