cmake: fix FindFontconfig.cmake - FONCONFIG_FOUND was not set, when FONTCONFIG_INCLUDE_DIRS was empty (on CentOS 6.5 for example)
As we have --std=c99 in CMAKE_C_FLAGS, to expose some macros and functions we should declare feature-check-marco...
Define _DARWIN_C_SOURCE should enable all mac os non standard extensions.
cmake: Disable try to link with static system installed libs, seems that linux distros not supported this option mostly
cmake: Add correct _POSIX_C_SOURCE and _BSD_SOURCE (linux) defines when build luasocket, so all types and func properly defined
Rewrite FindGLFW3.cmake, so it can found static glfw3 and link all deps.
pkg-config return include directory for use as '#include <GLFW/glfw3.h>', but we use '#include "glfw3.h"', fix include dir.
cmake: fixes for old cmake 2.8.12
remove some debug output
Update CHANGELOG
add some debug info
cmake: add policy CMP0017 to fix warnings on 2.8.8 cmake and set it to NEW for predictable include behaviour
Merge remote-tracking branch 'origin/v3' into cmake-linux-mac-fixes

* origin/v3:
  Update CHANGELOG
  Update AUTHORS
  fixed typo
  Updates definition of Complete.
  [AUTO][ci skip]: updating cocos2dx_files.json
  Revert "Merge pull request #9193 from pipu/v3_flatbuffers"
  Skip binding nodeWithFlatBuffers of CSLoader for lua
Additional debug info.
Add fresh FindPkgConfig.cmake for sure that vendors not overwrite it.
Remove debug info. And add warning message if pkg-config not found.
Merge pull request #9218 from vovkasm/cmake-linux-mac-fixes

Cmake linux mac fixes