Openenclave: Generate a visual of the CMake dependency graph

[andschwa]

It is possible to generate a visual of the CMake dependency graph with graphviz. We need to do this in order to move forward with fixing the dependency graph (since it will be a lot easier to reason about if we can see it as a graph instead of inspecting every target by hand).

[andschwa]

Here's how to generate it:

mkdir graphviz
cmake --graphviz=graphviz/graph .
dot graphviz/graph -T png -o graphviz/graph.png

But due to the thousands of test targets, right now this generates a picture which crashes Windows Photos.

[andschwa]

Here's how to generate it:

mkdir graphviz && cd graphviz
cmake --graphviz=graph ..
dot graph -Tsvg -o graph.svg

But due to the thousands of test targets, right now this generates a picture which crashes Windows Photos. Working on removing the extraneous targets.

[andschwa]

I generated an SVG instead of a PNG and can view it just fine. As GitHub doesn't support attaching SVGs, it is instead a zip: graph.zip

@CodeMonkeyLeet and @radhikaj might be particularly interested.