Don't expose filesystem list on /
Remove version from Makefile
Fix 404 errors after file ending change
Remove extra Sprintf call
Remove unused file
Use upload file extension when building name

Makes it easier to choose the correct program when viewing the files
that have been uploaded. For now we just take the extension from the
filename and lowercase it; in the future maybe it should be determined
from the file itself.
Don't expose local filesystem on invalid paths
Serve both download and upload from /
Add prefix to env vars
Initial implementation
Initial commit