Turn the node nid/title into a link fragment pointing to the node (especially useful on pages with multiple nodes).

Enhance dna_summary text.
Fix some minor bugs.

Fix bad classification of the default grant; tune informatory text; add explanation about rebuilding permissions.

#241060: by salvis. Implement an optional debug mode that displays much more information in the node_access entries block.

#91846 by Dave Cohen, rerolled by salvis. Add a second block to list the users with access to a node.

Added devel_node_access module.  Gives developers feedback as to what the node_access table contains.