CCEffects - Environment map transform fixes

The when computing the transform from the affected node to the environment map node,
do not look for the first render texture in the parent hierarchy (or the world if no render texture
exists). This works if the node and the environment are children of the render texture but it
does not work if the user has called begin/end on the render texture and rendered a subtree
manually.

Instead, find the common ancestor of the node and environment and find the transform from
one to another via that common ancestor.