Changed all the import statements in all modules in the examples

directory to import only what is needed.

This fix issue #464

Author: denisra

examples/fetch0.py

@@ -2,7 +2,7 @@
 
 import sys
 
-from asyncio import *
+from asyncio import get_event_loop, open_connection, coroutine
 
 
 @coroutine

examples/fetch1.py

@@ -6,7 +6,7 @@
 import sys
 import urllib.parse
 
-from asyncio import *
+from asyncio import get_event_loop, open_connection, coroutine
 
 
 class Response:

examples/fetch2.py

@@ -7,7 +7,7 @@
 import urllib.parse
 from http.client import BadStatusLine
 
-from asyncio import *
+from asyncio import get_event_loop, open_connection, coroutine
 
 
 class Request:

examples/fetch3.py

@@ -8,7 +8,7 @@
 import urllib.parse
 from http.client import BadStatusLine
 
-from asyncio import *
+from asyncio import get_event_loop, open_connection, coroutine
 
 
 class ConnectionPool:

examples/sink.py

@@ -4,7 +4,7 @@
 import os
 import sys
 
-from asyncio import *
+from asyncio import get_event_loop, coroutine, Protocol
 
 ARGS = argparse.ArgumentParser(description="TCP data sink example.")
 ARGS.add_argument(

examples/source.py

@@ -3,8 +3,7 @@
 import argparse
 import sys
 
-from asyncio import *
-from asyncio import test_utils
+from asyncio import test_utils, get_event_loop, coroutine, Protocol, Future
 
 
 ARGS = argparse.ArgumentParser(description="TCP data sink example.")

examples/source1.py

@@ -3,8 +3,7 @@
 import argparse
 import sys
 
-from asyncio import *
-from asyncio import test_utils
+from asyncio import test_utils, get_event_loop, coroutine, open_connection
 
 ARGS = argparse.ArgumentParser(description="TCP data sink example.")
 ARGS.add_argument(

examples/stacks.py

@@ -1,7 +1,7 @@
 """Crude demo for print_stack()."""
 
 
-from asyncio import *
+from asyncio import get_event_loop, open_connection, coroutine, Task, async
 
 
 @coroutine