The "mock" framework provides a base starting set
of support APIs such as Get/Put/Delete state and
Range for unit testing chaincodes. As tables are used
extensively, this change enhances the framework with
table support.

This addresses https://jira.hyperledger.org/browse/FAB-345



Change-Id: I3bb01e131b370d2e5140d73e022a5a519a4677f2
Signed-off-by: Srinivasan Muralidharan <muralisr@us.ibm.com>