Use terminology more consistently

[gilch]

I understand the concepts well enough to use Hissp, but communicating them is hard. I've started a glossary page on the wiki, and apparently some of the boundaries are muddied. This should probably be moved into the Sphinx docs.

Lissp compiles in stages. Lissp -> Hissp -> Python. That's typically token -> atom -> literal, for individual elements, but tags and macros complicate the picture. Often all three stages want to use the same name for a thing, since it represents the equivalent concept in the next stage. But in some cases, the distinction matters. Multiple token types read as str atoms, and str atoms can compile to any Python. Control words are str atoms, but are treated almost like a distinct type by the compiler.

I also want to use terminology that's consistent with other Lisps, but Lisp dialects aren't totally consistent with each other either, and that shouldn't come at the cost of clarity.

The glossary should help me nail down definitions so I can use the terms consistently in the docs, in the source code, and in the wiki. We're not there yet. Unfortunately, GitHub's Markdown dialect doesn't support definition lists, so I'm pretty much writing it in HTML. ReStructuredText is probably better at this.