Replace the graphNodeRoot for the main graph with a nodeCloseModule for
the root module. USe a new transformer as well, so as to not change any
behavior of DynamicExpand graphs.
Closing out the root module like we do with sub modules means we no
longer need the OrphanResourceTransformer, or the NodeDestroyResource.
The old resource destroy logic has mostly moved into the instance nodes,
and the remaining resource node was just for cleanup, which need to be
done again by the module since there isn't always a NodeDestroyResource
to be evaluated.
The more-correct state caused a few tests to fail, which need to be
cleaned up to match the state without empty resource husks.
When you specify `-verbose` you'll get the whole graph of operations,
which gives a better idea of the operations terraform performs and in
what order.
The DOT graph is now generated with a small internal library instead of
simple string building. This allows us to ensure the graph generation is
as consistent as possible, among other benefits.
We set `newrank = true` in the graph, which I've found does just as good
a job organizing things visually as manually attempting to rank the nodes
based on depth.
This also fixes `-module-depth`, which was broken post-AST refector.
Modules are now expanded into subgraphs with labels and borders. We
have yet to regain the plan graphing functionality, so I removed that
from the docs for now.
Finally, if `-draw-cycles` is added, extra colored edges will be drawn
to indicate the path of any cycles detected in the graph.
A notable implementation change included here is that
{Reverse,}DepthFirstWalk has been made deterministic. (Before it was
dependent on `map` ordering.) This turned out to be unnecessary to gain
determinism in the final DOT-level implementation, but it seemed
a desirable enough of a property that I left it in.
