by Dave Cohen: support markup for both connected and non-connected users on same page.  Avoids need for page refresh and works with Drupal page cache.

refs #1215624 by Dave Cohen: remove some (not yet all) references to apikey.  Facebook no longer provides it.

More robust fb.js.

Check login status on all requests.  Important for detecting logout when offline_access permission granted.

#701982 by mcpuddin: support fragments in reload_url.  Also, an unrelated change moving js settings back to hook_init.

sanity check to avoid infinite refresh

changed _fb_js_fbu param to avoid confict with "fb_..." params from old facebook api.  Still not working on canvas pages though.

Restored support for FBML popup dialogs.  Had been broken since 2.x->3.x upgrade.  Now using new FB.ui(...) javascript to support this.

Introducing "controls" as a way to customize behavior on certain pages and the ajax callbacks those pages generate.

Enable cookies on canvas pages, for some browsers it actually works!
Pass session to ajax callbacks, because on millions of browsers cookies dont work.

changed 'fb_session_no' to 'fb_session_handoff'
changed order of javascript event handling, hope to avoid bogus session change events.

framework for passing javascript events between fb.js and modules.  New hook_fb op for javascript events.