Initial commit: Simple Sensor firmware for Heltec T114 with BME280

- MeshCore-based Simple Sensor firmware
- Heltec T114 without display
- BME280 sensor support (temp/humidity/pressure)
- Radio: 868.856018 MHz, SF7, BW62.5 kHz, CR4/7
- 2-byte path hash
- PlatformIO project

variants/thinknode_m5/variant.h

@@ -0,0 +1,28 @@
+#define I2C_SCL 1
+#define I2C_SDA 2
+#define PIN_VBAT_READ    8
+#define AREF_VOLTAGE            (3.0)
+#define ADC_MULTIPLIER (2.11F)
+#define PIN_BUZZER 9
+#define PIN_VEXT_EN_ACTIVE HIGH
+#define PIN_VEXT_EN 46
+#define PIN_USER_BTN 21
+//#define PIN_LED 3
+//#define PIN_STATUS_LED 1
+#define PIN_PWRBTN 14
+
+#define PIN_DISPLAY_MISO               (-1)
+#define PIN_DISPLAY_MOSI               (45)
+#define PIN_DISPLAY_SCLK               (38)
+#define PIN_DISPLAY_CS                 (39)
+#define PIN_DISPLAY_DC                 (40)
+#define PIN_DISPLAY_RST                (41)
+#define PIN_DISPLAY_BUSY               (42)
+#define EXP_PIN_BACKLIGHT              (5)
+#define EXP_PIN_POWER                  (4)
+
+#define PIN_GPS_EN                      (11)
+#define PIN_GPS_RESET                   (13)
+#define PIN_GPS_RX                      (20)
+#define PIN_GPS_TX                      (19)
+#define PIN_GPS_SWITCH                  (10)