fix outdated documentation [ci skip]

cocos/2d/CCSprite.h

@@ -184,7 +184,7 @@ class CC_DLL Sprite : public Node, public TextureProtocol
      * A SpriteFrame will be fetched from the SpriteFrameCache by spriteFrameName param.
      * If the SpriteFrame doesn't exist it will raise an exception.
      *
-     * @param   spriteFrameName A null terminated string which indicates the sprite frame name.
+     * @param   spriteFrameName The name of sprite frame.
      * @return  An autoreleased sprite object.
      */
     static Sprite* createWithSpriteFrameName(const std::string& spriteFrameName);

cocos/base/CCProtocols.h

@@ -236,7 +236,7 @@ class CC_DLL LabelProtocol
     /**
      * Sets a new label using a string
      *
-     * @param label A null terminated string
+     * @param label The name of the new label.
      * @js NA
      * @lua NA
      */

cocos/renderer/CCTextureAtlas.h

@@ -67,7 +67,7 @@ class CC_DLL TextureAtlas : public Ref
     /** Creates a TextureAtlas with an filename and with an initial capacity for Quads.
 
      * The TextureAtlas capacity can be increased in runtime.
-     @param file A null terminated string contains the file path.
+     @param file The file path.
      @param capacity Capacity for Quads.
     */
     static TextureAtlas* create(const std::string& file , ssize_t capacity);
@@ -94,7 +94,7 @@ class CC_DLL TextureAtlas : public Ref
     * The TextureAtlas capacity can be increased in runtime.
     *
      @attention Do not reinitialize the TextureAtlas because it will leak memory (issue #706).
-     @param file A null terminated string contains the file path.
+     @param file The file path.
      @param capacity Capacity for Quads.
     */
     bool initWithFile(const std::string& file, ssize_t capacity);

cocos/renderer/CCTextureCache.h

@@ -110,7 +110,7 @@ class CC_DLL TextureCache : public Ref
     * Object and it will return it. It will use the filename as a key.
     * Otherwise it will return a reference of a previously loaded image.
     * Supported image extensions: .png, .bmp, .tiff, .jpeg, .pvr.
-     @param filepath A null terminated string.
+     @param filepath The file path.
     */
     Texture2D* addImage(const std::string &filepath);
 
@@ -119,7 +119,7 @@ class CC_DLL TextureCache : public Ref
     * Otherwise it will load a texture in a new thread, and when the image is loaded, the callback will be called with the Texture2D as a parameter.
     * The callback will be called from the main thread, so it is safe to create any cocos2d object from the callback.
     * Supported image extensions: .png, .jpg
-     @param filepath A null terminated string.
+     @param filepath The file path.
      @param callback A callback function would be invoked after the image is loaded.
      @since v0.8
     */