HTTP 1.0 response without Content-Length header is not properly handled

[emiliedns]

Hello,
First thank you a lot for your work!
Then, when I was writting unittest for my code which is using asks, I ran into (what I think is) a bug.
I used http.server which is HTTP 1.0 by default and which is not sending Content-Length header (spec says server doesn't have to on response if its closes the connection at the end of the message).
asks doesn't seems to cope with that:
Here is an example to reproduce the bug:
(if you uncomment the content-length line all will be fine)

from http.server import HTTPServer, BaseHTTPRequestHandler
import asks
import trio
import threading 
import time
class SimpleHTTPRequestHandler(BaseHTTPRequestHandler):

    def do_GET(self):
        print("get")
        response = b'Hello, world!'
        self.send_response(200)
        self.send_header('Content-type', 'text/html')
        #self.send_header('Content-length', len(response))
        self.end_headers()
        self.wfile.write(response)
        return

def start_server(path, port=8000):
    '''Start a simple webserver serving path on port'''
    httpd = HTTPServer(('localhost', 8000), SimpleHTTPRequestHandler)

    """httpd.socket = ssl.wrap_socket(httpd.socket,
                                   keyfile=f"{dir_test}/localhost.key",
                                   certfile=f"{dir_test}/localhost.crt", server_side=True)"""
    httpd.serve_forever()



async def main():
   daemon = threading.Thread(name='daemon_server',
                                  target=start_server,
                                  args=('.', 8000))
   daemon.setDaemon(True)  # Set as a daemon so it will be killed once the main thread is dead.
   daemon.start()
   time.sleep(1)
   r = await asks.get('http://localhost:8000/')
   print(r.content)

if __name__ == '__main__':
   trio.run(main)

I think this issue : #136 may be the same (at first my server was serving ssl and the error was looking the same than that)

Best regards,
Emilie.