Clients can cause the server to crash using malformed URLs

[pR0Ps]

Found in v0.4.5, seems to be fixed in the next branch.

To reproduce:

1. Run npx sirv start
2. Visit http://localhost:5000/%

Traceback:

/<redacted>/node_modules/sirv/index.js:81
			let stats, file, uri=decodeURIComponent(req.path || req.pathname || parser(req).pathname);
			                     ^

URIError: URI malformed
    at decodeURIComponent (<anonymous>)
    at Server.cc (/<redacted>/node_modules/sirv/index.js:81:25)
    at Server.emit (events.js:327:22)
    at parserOnIncoming (_http_server.js:789:12)
    at HTTPParser.parserOnHeadersComplete (_http_common.js:116:17)

[lukeed]

Closed via #64