Fixes DE226: refactor node attribute/search logic

This provider had two large 'if' conditionals that each set node
attributes and searched for other nodes.  The problem was that the
current node was never included in the fun first-time around (even if it
wanted to be, there was a chicken-egg problem with doing the node
searches before the current node's attributes were set).

I broke the logic into "setting attributes" and then "searching nodes
and generating file data."  I modified the search functions to include
the current node if necessary (take a hike, run_twice). I commented the
logic and added debugging statements. I renamed/added variables and
renamed get_pubkey() to configure_pubkey() (more accurate to its
function). Touched up a couple minor style things and trivial bugs
(eg., unnecessary call to node.save). Tested the hell out of it.
Merge pull request #26 from invsblduck/de226

Merged automatically by jenkins after successful build test
Fixes DE240: bugfix: stale keys cannot be detected

don't wipe the group-name hash every time.
Merge pull request #27 from invsblduck/de240

Merged automatically by jenkins after successful build test
Fixes DE243: accurately fire notifies for resource update

use_inline_resources
Merge pull request #28 from invsblduck/de243

Merged automatically by jenkins after successful build test
(Fixes DE245) manage $HOME/.dsh/group/<file>

converted to actual file resource.
Merge pull request #29 from invsblduck/de245

Merged automatically by jenkins after successful build test