Rewrite of the connection setup.

I'd want to advice against using `use_connection()` more, as the
connection setup is less explicit, and also pollutes global memory.

Because, well:

    $ python -m this | head -n4 | tail -n1

;)

examples/run_example.py

@@ -1,34 +1,40 @@
 import os
 import time
-from rq import Queue, use_connection
+from rq import Queue, Connection
 from fib import slow_fib
 
-# Tell RQ what Redis connection to use
-use_connection()
-# Range of Fibonacci numbers to compute
-fib_range = range(20, 34)
 
-# Kick off the tasks asynchronously
-async_results = {}
-q = Queue()
-for x in fib_range:
-    async_results[x] = q.enqueue(slow_fib, x)
+def main():
+    # Range of Fibonacci numbers to compute
+    fib_range = range(20, 34)
 
-start_time = time.time()
-done = False
-while not done:
-    os.system('clear')
-    print 'Asynchronously: (now = %.2f)' % (time.time() - start_time)
-    done = True
+    # Kick off the tasks asynchronously
+    async_results = {}
+    q = Queue()
     for x in fib_range:
-        result = async_results[x].return_value
-        if result is None:
-            done = False
-            result = '(calculating)'
-        print 'fib(%d) = %s' % (x, result)
-    print ''
-    print 'To start the actual in the background, run a worker:'
-    print '    python examples/run_worker.py'
-    time.sleep(0.2)
+        async_results[x] = q.enqueue(slow_fib, x)
 
-print 'Done'
+    start_time = time.time()
+    done = False
+    while not done:
+        os.system('clear')
+        print 'Asynchronously: (now = %.2f)' % (time.time() - start_time)
+        done = True
+        for x in fib_range:
+            result = async_results[x].return_value
+            if result is None:
+                done = False
+                result = '(calculating)'
+            print 'fib(%d) = %s' % (x, result)
+        print ''
+        print 'To start the actual in the background, run a worker:'
+        print '    python examples/run_worker.py'
+        time.sleep(0.2)
+
+    print 'Done'
+
+
+if __name__ == '__main__':
+    # Tell RQ what Redis connection to use
+    with Connection():
+        main()

examples/run_worker.py

@@ -1,8 +1,8 @@
-from rq import Queue, Worker, use_connection
+from rq import Queue, Worker, Connection
 
-# Tell rq what Redis connection to use
-use_connection()
 
 if __name__ == '__main__':
-    q = Queue()
-    Worker(q).work()
+    # Tell rq what Redis connection to use
+    with Connection():
+        q = Queue()
+        Worker(q).work()