Fix an issue with a broken headers list when generating ".clang_complete" for Emacs // Resolve #1960

HISTORY.rst

@@ -9,6 +9,8 @@ PlatformIO 3.0
 
 * Ignore *.asm and *.ASM files when building Arduino-based library (compatibility with Arduino builder)
 * Fixed spurious project's "Problems" for `PlatformIO IDE for VSCode <http://docs.platformio.org/page/ide/vscode.html>`__ when ARM mbed framework is used
+* Fixed an issue with a broken headers list when generating ".clang_complete" for `Emacs <http://docs.platformio.org/page/ide/emacs.html>`__
+  (`issue #1960 <https://github.com/platformio/platformio-core/issues/1960>`_)
 
 3.6.2 (2018-11-29)
 ~~~~~~~~~~~~~~~~~~

platformio/ide/tpls/emacs/.clang_complete.tpl

@@ -1,5 +1,5 @@
 % for include in includes:
--I"{{include}}"
+-I{{include}}
 % end
 % for define in defines:
 -D{{!define}}