Extract overgrown parts of parser and emitter into their own areas

Parser and emitter are the two largest files in the interpreter. They both do a lot, so that's to be expected. When I add a new part or file to the interpreter, it's usually from splitting off some part of one of the above two. Importing was recently split away from parser. These splits are typically ad-hoc and limited to one area, so I don't usually attach an issue.

Parser's manifest is inside of parser because it was easy to do it that way. I distinctly recall when I originally set out to do it, I expected it to be much smaller. Although it shares some underlying parts with parser's core, there's a fair amount that belongs to it alone.

Dynaload's implementation bits ought to be in a file themselves. I suspect that I'll need to create a parser core, containing parts like type collection and common shared bits, and extract that as well. Which is fine. I'm noticing it's becoming more and more difficult to peruse parser as it becomes larger and the non-parsing parts become larger.

For emitter, I'd like to move block handling out. Parser and emitter have this peculiar overlap with lambda handling. If it makes sense, I'd like to get lambda processing primarily in one area. It's, at times, odd to jump between the two of them to resolve how a lambda is processed.