Added support for requesting arbitrary files from webserver
SimpleHttpServer.java:
-added ResourceHandler (url: /resource?file=path/to/some/file) to handle request for arbitrary files
-strips any relative path structures from requested file path ("../" -> "")
-file path is relative to the website resources folder

index.html:
-moved javascript code to seperate file now that it can be loaded separately
-added prefix 'resource?file=' to all urls