rs: code friendly keymap for preonic, iris and my preonic clone (#4303)

I worked on those keymap to simplify the use of 60% keyboards for
coders. Instead of trying to mimic planck, this keymap remove
raise/lower layer complexity and keep some important sign keys for coder
in the upper right side pretty much the same way as they are on a full
keyboard.

A karabiner configuration is also provided to mimic most of the keymap
features on the macbook internal keyboard for when you are forced to use
it.

keyboards/iris/keymaps/rs/config.h

@@ -0,0 +1,38 @@
+/*
+Copyright 2017 Danny Nguyen <danny@hexwire.com>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#pragma once
+
+/* Use I2C or Serial, not both */
+
+#define USE_SERIAL
+// #define USE_I2C
+
+/* Select hand configuration */
+
+#define MASTER_LEFT
+// #define MASTER_RIGHT
+// #define EE_HANDS
+
+#define TAPPING_TERM 150
+
+#undef RGBLED_NUM
+#define RGBLED_NUM 6
+#define RGBLIGHT_SLEEP
+#define RGBLIGHT_HUE_STEP 1
+#define RGBLIGHT_SAT_STEP 1
+#define RGBLIGHT_VAL_STEP 1