tilemap supports XML layer format
a potential bug in Layer.

https://github.com/cocos2d/cocos2d-x/issues/2948
Update CCLayer.cpp

change "_accelerometerEnabled = false"
to "setAccelerometerEnabled(false)"
in method init().
a potential bug in ScrollView

check _touches in setTouchEnabled
the latest develop code merged
Merge branch 'develop' of https://github.com/cocos2d/cocos2d-x into tilemap_plain_xml_format_support
added _currentTileIndex member to TMXLayerInfo
removed extra _currentTileIndex
Fix for #2892.
1. Updatet the API documentation and parameter name from "object" to "sender" to reflect it's true purpose.
2. Fixed addObserver and observerExisted because it didn't allowed to add observers to notifications that only differs by sender
Fix for #2892.
3. Fixed registerScriptObserver method.
Adding tools/tolua .
Updating bindings-generator, adding lua target. It's not finished.
We has to pass the target to bindings-generator since we have add lua target.
Adding tools/tolua .
issue #2433:lua binding generator
Merge branch 'iss2433-lua-bindings-generator' of git://github.com/dumganhar/cocos2d-x into iss2433-lua-bindings-generator
Fixed broken links and wrong encoding in the doc.

Fixed Obj-C names when referening functions.
Changed some GB2312 encoded characters to UTF-8.
Changed two 'XXX class for cocos2d for iphone'.
issue #2433:lua binding generator add hello.lua
Documentation & Cocos2d-x C++ Style