Split up pins to make it more manageable

Hopefully this is helpful to organization and future expansion….

Marlin/pins_GEN7_14.h

@@ -0,0 +1,60 @@
+/**
+ * Gen7 v1.4 pin assignments
+ */
+
+#define GEN7_VERSION 14 // v1.4
+
+#if !defined(__AVR_ATmega644P__) && !defined(__AVR_ATmega644__) && !defined(__AVR_ATmega1284P__)
+  #error Oops! Make sure you have 'Gen7' selected from the 'Tools -> Boards' menu.
+#endif
+
+//x axis pins
+#define X_STEP_PIN 29
+#define X_DIR_PIN 28
+#define X_ENABLE_PIN 25
+#define X_STOP_PIN 0
+
+//y axis pins
+#define Y_STEP_PIN 27
+#define Y_DIR_PIN 26
+#define Y_ENABLE_PIN 25
+#define Y_STOP_PIN 1
+
+//z axis pins
+#define Z_STEP_PIN 23
+#define Z_DIR_PIN 22
+#define Z_ENABLE_PIN 25
+#define Z_STOP_PIN 2
+
+//extruder pins
+#define E0_STEP_PIN 19
+#define E0_DIR_PIN 18
+#define E0_ENABLE_PIN 25
+
+#define TEMP_0_PIN 1
+#define TEMP_1_PIN -1
+#define TEMP_2_PIN -1
+#define TEMP_BED_PIN 0
+
+#define HEATER_0_PIN 4
+#define HEATER_1_PIN -1
+#define HEATER_2_PIN -1
+#define HEATER_BED_PIN 3
+
+#define KILL_PIN -1
+
+#define SDPOWER -1
+#define SDSS -1 // SCL pin of I2C header
+#define LED_PIN -1
+
+#define FAN_PIN -1
+
+#define PS_ON_PIN 15
+
+//our pin for debugging.
+#define DEBUG_PIN 0
+
+//our RS485 pins
+#define TX_ENABLE_PIN 12
+#define RX_ENABLE_PIN 13
+