Factor common code out of the test fake sources

* * *
More fake source refacoring

tests/fakes/source/connect_during_hello.rb

@@ -1,34 +1,17 @@
 #!/usr/bin/env ruby
 
 # Connect to the destination, then hang.  Connect a second time to the
-# destinatioin.  This will trigger the destination's thread clearer.
+# destination.  This will trigger the destination's thread clearer.
 
-require 'socket'
-require 'timeout'
+require 'flexnbd/fake_source'
+include FlexNBD::FakeSource
 
 addr, port = *ARGV
 
 # client_sock1 is a connection the destination is expecting.
-client_sock1 = nil
-begin
-  Timeout.timeout(2) do
-    client_sock1 = TCPSocket.open( addr, port )
-  end
-rescue Timeout::Error
-  $stderr.puts "Timed out connecting."
-  exit 1
-end
-
-#client_sock2 is the interloper.
-client_sock2 = nil
-begin
-  Timeout.timeout(2) do
-    client_sock2 = TCPSocket.open( addr, port )
-  end
-rescue Timeout::Error
-  $stderr.puts "Timed out connecting a second time."
-  exit 1
-end
+client_sock1 = connect( addr, port, "Timed out connecting" )
+sleep(0.25)
+client_sock2 = connect( addr, port, "Timed out connecting a second time" )
 
 # This is the expected source crashing after connect
 client_sock1.close