Add examples/simple-http.py (#32)

Sort of like a very simple HTTPie

e.g.:

```
$ examples/simple-http.py http+unix://%2Fvar%2Frun%2Fdocker.sock/version
{"Version":"1.12.3","ApiVersion":"1.24","GitCommit":"6b644ec","GoVersion":"go1.6.2","Os":"linux","Arch":"amd64","KernelVersion":"4.4.0-63-generic","BuildTime":"Mon, 19 Dec 2016 09:20:48 +1300"}
```

Author: msabramo

examples/simple-http.py

@@ -0,0 +1,11 @@
+#!/usr/bin/env python
+
+import sys
+
+import requests_unixsocket
+
+session = requests_unixsocket.Session()
+
+url = sys.argv[1]
+res = session.get(url)
+print(res.text)