Support packages with more than one file

[ericoporto]

Dialog Module.zip
https://www.adventuregamestudio.co.uk/forums/index.php?topic=48218.0

The above module also packs a GUI to be used alongside, for now we don't support this, need to figure out how and what would be it's package.json annotation.

Alternatively, each content could be packaged separately and a bundle type package could be an empty package that just depends on both.