[FAB-2814] Change default batch timeout to 2s

https://jira.hyperledger.org/browse/FAB-2814

There have been a number of requests to reduce the default batch timeout
from its current default of 10s to something more appropriate for demos.

This CR changes the default from 10s, to the v0.6 default of 2s.

Change-Id: Id08af41dc3fca2a4e5659f5a0b4c9349adfb5141
Signed-off-by: Jason Yellick <jyellick@us.ibm.com>

common/configtx/tool/configtx.yaml

@@ -102,7 +102,7 @@ Orderer: &OrdererDefaults
         - 127.0.0.1:7050
 
     # Batch Timeout: The amount of time to wait before creating a batch.
-    BatchTimeout: 10s
+    BatchTimeout: 2s
 
     # Batch Size: Controls the number of messages batched into a block.
     BatchSize: