Implement leaf page compiler.

[bigeasy]

Create a utility that will rewrite a leaf page that someone edits in an editor after a catastrophe. If something terrible happens, and the CRCs are reporting errors, we don't want to have to provide an auto recovery. Let the application programmer jump into action, because if you can read the JSON, see corruption, edit it and rebuild, that might get a project back on the rails, that might be all it takes.

What good are CRCs if there is no recovery mode? How am I supposed to imagine a recovery procedure for a database when all I've written is a b-tree. This is ment to be dealt with at a higher level. Strata only needs to provide utilities resume from inputs blessed by higher authority.