Made liftAjax.js and liftComet.js a single static .js file.
Fixed hard-coded LiftRules.resourceServerPath
Send basic JS info in data- attributes.

This includes the page version, session id, and comet ids and
versions. The data- attributes are set and read on the body
element of the page.
Remove enableGc from LiftJavaScript config.

We now decide whether or not GC is enabled by the presence
of a data-lift-gc attribute.
Redo body attribute calculation.
Move page-specific JS into a RequestVar.

The RequestVar contains a JavaScriptResponse, though it
isn’t yet hooked up. Looking up /lift/<page id>.js will return the
file in that RequestVar, if present.
Replace ajaxPath/cometPath with liftPath.

liftPath is now the root of Lift requests, and everything under
it is under our control. AJAX lives at $liftPath/ajax and comet
at $liftPath/comet. Additionally, we drop ajax and comet from
the JSArtifacts. These functions are now provided directly by
lift.js.
Drop ScriptRenderer, which is no longer used.
Move LiftMerge#scriptUrl to liftPath.
Namespace page script under $liftPath/page/*
Fix compile error with page inclusion check.
Fix construction of body attributes.

We had switched to half-String half-Option[String], breaking
compilation; it’s all String now.
Added Promise code to lift.js
Add dispatch for per-page JS.
Uppercase GUID in comet data attributes.
Fix initial comet registering in lift.js
Add and use lift.onDocumentReady function.

jQuery’s just assigns to $(document).ready, while the vanilla
one uses Diego Perini’s contentloaded script to set things
up.
Drop window.liftAjax legacy compatibility layer.
javaScriptSettings returns Box[LiftSession=>JsObj]

We remove autoIncludeJSSettings in favor of an Empty Box
returned from javaScriptSettings; we also fix the
capitalization of javaScriptSettings (it was
javascriptSettings).
Merge pull request #1559 from lift/outline-scripts

Outline Scripts: Refactor JS support to a single static file + move initialization to per-page file.

Two major things here:

 - JS support is now in a single lift.js file at resources/toserve. Initialization is done via the
   LiftRules.javascriptSettings rule.
 - JavaScript added to the page via S.appendJs is now accumulated into a separately
   referenced JS file that is served once.