Major redesign of rendering pipeline that separates pages saved with MCE from pages saved with the plaintext editor (full description in long commit message) - Pages are now stored with an extra metadata field called page_format which is "wikitext" or "xhtml" - New $flags parameter + RENDER_* constants added that control RenderMan::render() behavior - Several other changes: * Added a sprite API for Javascript and made editor use sprites when possible * Removed a number of config options from the default install schema, replaced with second parameter to getConfig() calls * MessageBox in editor mostly replaced with miniPrompt * A few bugfixes related to password changes (registration didn't even work) * Rewrote the bitfield compression algorithm used to serialize allowed MIME types * Fixed some typos in language files and strings * Fixed a Text_Wiki bug in Heading parser