Allow Modules to load multiple JS files in debug mode

[rcatalano]

My app makes heavy use of modules. In debug mode, the list of scripts in the debugger looks like this:

It's a little unwieldy. I'd like to see the files that make up my modules individually.

There are two parts to implementing this:

1. SC.Module._loadJavaScriptForModule needs to support scriptURL and stringURL properties that are arrays. Like in _loadCSSForModule, it would loop over the arrays and load each file, calling _moduleDidLoad when all files have been loaded.
2. Build tools (abbot or the new BT) should generate SC.MODULE_INFO that contains scriptURL and stringURL arrays. They also need to make sure the individual files are accessible by the URLS it provides to SC.MODULE_INFO.

At this point I don't see much value in implementing this in Abbot. I have already spoken with mauritslamers about implementing this is the new BT. Once the support is added to the framework, we can tackle the BT side.