issue fixes

#61 added setting to config file to allow audio threshold to be changed. Untested

#58 Added full screen option to world view. We need a way to resize the unity window, perhaps when we have the new unity version it'll be easier.

Edited app.js to use the default world template for all worlds, that way created worlds got the world view changes. This settings needs updating, it was using a custom world view even if the user never set one.