Merge branch 'release/NzljYT'
Merge branch 'release/YTdhNj'
Update README.md
Added an import for cocos2d.h if CC_DIRECTOR is not declared
Amended README
Update iAdHelper.h

Added an option to display iAD on top or bottom of the screen
Update iAdHelper.m

Added an option to display ad on top or bottom
Update iAdHelper.h

Corrected info block
Update iAdHelper.m

Corrected info block
Update README.md
better README