specialize RenderCommandPool<QuadCommand>
use raw new instead of generateCommand
Specialize GroupCommand and CustomCommand, change generateCommand to new.
Merge pull request #1 from boyu0/develop_removeCommandPool

Specialize GroupCommand and CustomCommand, change generateCommand to new...
change QuadCommand variable to class member.
change GroupCommand variable to class member.
delete ‘delete ptr’ and add CC_UNUSED_PARAM
change CustomCommand variable to class member.
fix bug.
Merge pull request #2 from boyu0/develop_removeCommandPool

Develop remove command pool
remove commandPool in renderCommand
adjust comment codes
remove empty interface releaseToCommandPool
Merge branch 'develop' into develop_removeCommandPool

* develop: (33 commits)
  fix black screen when back to foreground  on android.
  Fix set FPS broken.
  Update CHANGELOG [ci skip]
  Update AUTHORS [ci skip]
  Update CCString.cpp
  [AUTO] : updating submodule reference to latest autogenerated bindings
  Updates Bindings-generator.
  Renames: IntValueMap —> ValueMapIntKey
  Restricts the element type for Vector<T> and Map<K, V>, it has to be `Object*` or `ObjectSubClass*`.
  Modify reader
  long --> ssize_t for TableView callback.
  Generates execute file in cocos root_dir/bin folder for HelloCpp.
  Add listview and pageview  reader
  [AUTO] : updating submodule reference to latest autogenerated bindings
  Modify actionnode
  [AUTO] : updating submodule reference to latest autogenerated bindings
  optimize loop
  fix LabelTestNew
  Compilation fixes after merge PR #4669 https://github.com/cocos2d/cocos2d-x/pull/4669
  Fix box2dView
  ...
fix testcase remove commandpool
Merge pull request #4728 from dabingnn/develop_removeCommandPool

Develop remove command pool