Update bindings-generator and `MAX_SUB_TEST_NUMS`  for SpritePerformance Test
Merge branch 'v3' of https://github.com/cocos2d/cocos2d-x into v3_fix
issue #5032:A potential crash bug of Lua binding
Merge branch 'v3' of https://github.com/cocos2d/cocos2d-x into v3_lua_fix
Merge branch 'v3' of https://github.com/cocos2d/cocos2d-x into v3_fix
Update the bindings-generator
Update bindings-generator submodule
Merge branch 'v3' of https://github.com/cocos2d/cocos2d-x into v3_fix
download-deps.py will unzip the download zip file.
Output more detail informations
Delete external submodule, please use 'download-deps.py' instead.
Re-adds box2d and chipmuck sources, we need to use prebuilt libraries for them too.
Adds external/version.txt
Updates .gitignore.
updates travis-script.
add some comment for dependences module in Android.mk to make it simple to use other module
:= -> +=
Merge pull request #6598 from minggo/android-makefile

add some comment for dependences module in Android.mk to make it simple ...
Updates .gitignore, ignore version.json
Updates travis script
download-deps.py supports to check 'external/version.json'