Merge branch 'develop' into feature/platformio-30

* develop:
  Fix issue with ``platformio init --ide`` command for Python 2.6
  Version bump to 2.10.3
  Fix issue with appending PIO version to Build Defines
  Add test for `init --ide eclipse`
  Version bump to 2.10.2 (issues #695)
  Fix firmware uploading to Arduino/Genuino 101 // Resolve #695
  Use $PLATFORM from build environment instead from the board config
  Update Intel ARC32 Arduino framework to v1.0.6 // Issue #695
  Update Intel ARC32 Arduino framework to v1.0.6
  Add support for ST Nucleo L031K6 board to ARM mbed framework
  Revert mcu option for genuino101
  Update intel_arc32 platform
  Update HISTORY.rst
  Fix upload size checker
  Process "$BUILD_UNFLAGS" variable
  Restore PIO macros if it was deleted by framework

docs/platforms/embedded_boards.rst

@@ -2013,6 +2013,13 @@ ST
       - 512 Kb
       - 128 Kb
 
+    * - ``nucleo_l031k6``
+      - `ST Nucleo L031K6 <https://developer.mbed.org/platforms/ST-Nucleo-L031K6/>`_
+      - STM32L031K6T6
+      - 32 MHz
+      - 32 Kb
+      - 8 Kb
+
     * - ``nucleo_l053r8``
       - `ST Nucleo L053R8 <https://developer.mbed.org/platforms/ST-Nucleo-L053R8/>`_
       - STM32L053R8T6

docs/platforms/ststm32.rst

@@ -357,6 +357,13 @@ ST
       - 512 Kb
       - 128 Kb
 
+    * - ``nucleo_l031k6``
+      - `ST Nucleo L031K6 <https://developer.mbed.org/platforms/ST-Nucleo-L031K6/>`_
+      - STM32L031K6T6
+      - 32 MHz
+      - 32 Kb
+      - 8 Kb
+
     * - ``nucleo_l053r8``
       - `ST Nucleo L053R8 <https://developer.mbed.org/platforms/ST-Nucleo-L053R8/>`_
       - STM32L053R8T6