log full `GET` request info

it's more useful to log the entire "RequestURI" than just log "Path"
```
root# go run main.go 
2014/12/21 18:04:27 macaron server running...
[Macaron] listening on 0.0.0.0:5000 (production)
[Macaron] Started GET /info?a=abc for [::1]
[Macaron] Completed /info?a=abc 200 OK in 684.427us
```