Provide an initial rough structure for the specification so we can add things
as they are decided.
Split the specification into a language and a library section. In the language
section, use one file per broad area of functionality. Divide the language up
based on the intended layering of the language design.
The original header was exactly 80-columns which made every file format
with a line-start comment syntax reflow the text. Instead, pick
a canonical re-flowing that keeps it to just three lines. This also lets
the text refer to the project which seems more clear.
No practical or semantic change here, just getting consistent wording
and line breaks for regularity.