Merge branch 'develop' into feature/platformio-30

* develop: (21 commits)
  Use stable docs
  Version bump to 2.11.2 (issues #500, #533, #732, #731, #737, #733, #438, #722, #52, #725)
  Update project configuration template
  Use stable docs
  Implement firmware merging with base firmware for Nordic nRF51 development platform // Resolve #500 , Resolve #533
  Fix firmware uploading to Atmel SAMD21-XPRO board using ARM mbed framework // Resolve #732
  Add firmware merging process for nordicnrf51 // Issue #533, #500
  Add OpenOCD as an alternative upload method for atmelsam platform // Issue #732
  Sync flags parser with PlatformIO 3.0 branch // Resolve #738
  Update ``udev`` rules for the new STM32F407DISCOVERY boards // Resolve #731
  Add explanation about "Failed to find MSBuild toolsets directory"
  Add support for local "--echo" for Serial Port Monitor // Resolve #733
  Update history
  Improve support for Microchip PIC32 development platform and ChipKIT boards // Resolve #438
  Fix Project Generator for ESP8266 and ARM mbed based projects
  Switch to gcc-built LwIP library for espressif platform
  Push 2.11.2.dev2
  Fix linking process for microchippic32 platfrom // Issue #438
  Improve Project Generator for PlatformIO IDE (fixes incorrect linter errors)

docs/quickstart.rst

@@ -146,24 +146,12 @@ The result of just generated ``platformio.ini``:
 .. code-block:: ini
 
     #
-    # Project Configuration File
+    # PlatformIO Project Configuration File
     #
-    # A detailed documentation with the EXAMPLES is located here:
-    # http://docs.platformio.org/en/latest/projectconf.html
+    # Please make sure to read documentation with examples first
+    # http://docs.platformio.org/en/stable/projectconf.html
     #
 
-    # A sign `#` at the beginning of the line indicates a comment
-    # Comment lines are ignored.
-
-    # Simple and base environment
-    # [env:mybaseenv]
-    # platform = %INSTALLED_PLATFORM_NAME_HERE%
-    # framework =
-    # board =
-    #
-    # Automatic targets - enable auto-uploading
-    # targets = upload
-
     [env:uno]
     platform = atmelavr
     framework = arduino