Fix weird color blending on using CCFadeOut; Add example of using CCAction classes with CCSkeleton

In `CCSkeleton.cpp`, set:

    blendFunc.src = GL_SRC_ALPHA;
    blendFunc.dst = GL_ONE_MINUS_SRC_ALPHA;

Instead of:

    blendFunc.src = CC_BLEND_SRC;
    blendFunc.dst = CC_BLEND_DST;

This is the same as `CCSprite.cpp` lines 164 & 165