fixed request parse error.

When parsing The below example request, Network.Parser.Rfc2616.request, fails.

```
"GET /search?q=haskell HTTP/1.1\r\nHost: www.google.co.jp\r\nUser-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:29.0) Gecko/20100101 Firefox/29.0\r\nAccept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8\r\nAccept-Language: ja,en-us;q=0.7,en;q=0.3\r\nAccept-Encoding: gzip, deflate\r\nCookie: PREF=ID=7ca99b92f2f9afe9:FF=0:TM=1400941989:LM=1400941989:S=w2rcVppuXeOj6pXi; NID=67=N3XLJvzIIHqfvn_LuNTgBmA59ni-8YNTZ-RFASwaaByYQ9q0wfljtVHijfzQIGVJQ8axRzvOoBI9idcimOPUVI4obXncxIUUVf17AgubzR8KFBQVlXb7n2S0LNV43EPV\r\nConnection: keep-alive\r\n\r\n"
```
pathAbsolute returns  "?q=haskell HTTP/1.1\n" then next parser fails

```
λ:  parseTest requestLine "GET  /search?q=haskell HTTP/1.1\n" 
Fail "?q=haskell HTTP/1.1\n" ["space","32"] "Failed reading: satisfyElem"
```