test backend

[morkeltry]

test that any given url passed to router module is either routed to a request for a file, or a request to an API, or generates and error for example:

• [ ] handlers.js should block illegal characters
• [ ] handlers.js should give 404 on directory traversal using ../../.. etc
• [ ] 404 on bad file name
• [ ] API URLs get sent to apiRequest
• [ ] correctly formatted file names provide file data