tests: use absolute_import in tinyproxy

Thus begins a series of adding absolute_import to a bunch of files for
Python 3 compatibility.

tests/test-check-py3-compat.t

@@ -220,5 +220,4 b''
   tests/test-url.py requires print_function
   tests/test-walkrepo.py requires print_function
   tests/test-wireproto.py requires print_function
-  tests/tinyproxy.py not using absolute_import
   tests/tinyproxy.py requires print_function

tests/tinyproxy.py

@@ -1,5 +1,7 b''
 #!/usr/bin/env python
 
+from __future__ import absolute_import
+
 __doc__ = """Tiny HTTP Proxy.
 
 This module implements GET, HEAD, POST, PUT and DELETE methods
@@ -12,7 +14,12 b' Any help will be greatly appreciated. '
 
 __version__ = "0.2.1"
 
-import BaseHTTPServer, select, socket, SocketServer, urlparse, os
+import BaseHTTPServer
+import os
+import select
+import socket
+import SocketServer
+import urlparse
 
 class ProxyHandler (BaseHTTPServer.BaseHTTPRequestHandler):
     __base = BaseHTTPServer.BaseHTTPRequestHandler