Multiple code_url and externs_url

[probins]

The options passed to the compiler is a JS object, meaning that a property can only occur once. code_url and externs_url can however occur multiple times. Perhaps define these as an array, and have the plugin convert those into multiple params?

And of course if code_url(s) is defined, there won't be js_code. :-)

[gavinhungry]

@probins, try it out now! Pass null as the first argument to compile if you don't need to specifiy js_code.

[probins]

yeah, that seems to work nicely thanks.

Perhaps update the readme too?

[gavinhungry]

@probins,

Turns out this won't work. I'm encoding everything as part of the URL, and with a longish file, it will now fail. Looking into this again.