Move check for the enabled flag down to the parse function
Move check for the enabled flag down to the parse function

If attrs are deemed _disabled_, the node itself will not be included in
the context tree. The reason for a node being disabled could be due to
an error which would cause the Node instance to be potentially unstable.
Moving the check to the parse function prevents this issue.

murphyke/avocado,murphyke/avocado,murphyke/avocado,murphyke/avocado