Comments: minor update.
Updated CMS_NODE_STORAGE_I API.
Delete a node using a node as formal parameter instead of node id.
Clean code and update log information.
Added precondition to delete node to accept nodes with a valid a id.
Added missing assertions tag names.
Updated node extension implementation.
Updated known permissions for node module.
Improved code for node storage extension , in preparation to code factorization.
Ensured that author is updated when saved.
