update changelog

Author: hathach

changelog.md

@@ -9,7 +9,9 @@
 - Updated for latest Bluefruit LE Connect version with RGBW support
 - Fix #48 SPI & I2C warnings
 - Change board define from ARDUINO_FEATHER52 to ARDUINO_NRF52_FEATHER (ARDUINO_FEATHER52 still exists for backward comaptiable)
-- change pin in hwpwm and hid_camerashutter sketches
+- Change pin in hwpwm and hid_camerashutter sketches
+- Update nffs code to mynewt v1.0.0
+- Add Realtrace support using Segger Sysview
 
 ## 0.6.0