title: Cocos2d-x-3.1.1 gives error while running build_native.py
body: <pre><code>python G:/ace/proj.android/build_native.py all 
  E:\android' is not recognized as an internal or external command,
  operable program or batch file.
  The Selected NDK toolchain version was 4.8 !
  Traceback (most recent call last):
  File "G:/ace/proj.android/build_native.py", line 166, in &lt;module&gt;
  build(opts.ndk_build_param,opts.android_platform,opts.build_mode)
  File "G:/ace/proj.android/build_native.py", line 153, in build
  do_build(cocos_root, ndk_root,         app_android_root,ndk_build_param,sdk_root,android_platform,build_mode)
  File "G:/ace/proj.android/build_native.py", line 89, in do_build
  raise Exception("Build dynamic library for project [ " + app_android_root + " ]   fails!")
  </code></pre>
  
  <p>Exception: Build dynamic library for project [ G:\ace\proj.android ] fails!</p>
  
  <p>This is the error, all paths are set and everything is up to date, NDK is R9D (64 bit) sdk etc all updated. I don't know know to fix this, on windows 7 64 bit, with eclipse and Cocos2d-x-3.1.1, all the paths are set using setup.py and verified working by running the setup.py</p>
  
  <p>Thanks </p>