Per entry lock

I still get errors like this:
'''
Exception in thread Thread-417:
Traceback (most recent call last):
  File "/usr/lib/python3.3/threading.py", line 637, in _bootstrap_inner
    self.run()
  File "/usr/lib/python3.3/threading.py", line 594, in run
    self._target(*self._args, **self._kwargs)
  File "./Proxy.py", line 372, in __init__
    self.request = ClientRequest(self.client_conn, address, strip_cache_headers, strip_user_agent)
  File "./Proxy.py", line 285, in __init__
    self.decoded_client_request = HttpRequest(bytes.decode(local_conn.recv(BUFFER_LENGTH)))
  File "./Proxy.py", line 206, in __init__
    firstline_split = (decoded_request).splitlines()[0].split()
IndexError: list index out of range
'''
But I think that this error happens for the code in the master branch, as well, so it might not be a result of my changes.