PR #55 Continued

See #55

I'm back! This should work.

* Recursive inclusion of a subgraph would yield segmentation fault due to lack of termination case and so need to avoid.
* Subgraph needs to be on a stand-alone line to prevent (very) rare cases in which, say, you want that pattern of text inside an initializer.

However, I haven't included the test case because I realized that it's still four spaces. Do you want me to include it here?

* Finally add a test case to test/, which I wasn't aware before. :p