APIDump: Fixed bad for-loop.

How did I not see this before?
APIDump: Added the WritingPlugin article to the exported pages.
APIDump: Fixed the WritingPlugin article.

The code is no longer weirdly indented in the browser, and links are relative to the API docs root.
APIDump: Extra pages renamed to articles and moved to front.
APIDump: Split the huge DumpAPIHtml function into smaller ones.
APIDump: Added a quick-nav menu to class descriptions.

First part of #403.
APIDump: Added a quick-nav menu to hook descriptions.

Second part of #403.
APIDump: Added quick links to index to each class and hook file.

Third part of #403.
APIDump: Articles eplicitly declare being UTF-8.

This fixes display in firefox.
APIDump: Added the SettingUpDecoda article.

This implements #383.
Fixed the Windows script for uploading Lua API to an FTP server.

The new script handles subfolders, too.