https://jira.hyperledger.org/browse/FAB-2925



This the first of CRs for "Chaincode Install Packaging"
story (FAB-2859).

Key changes below.

Note that these core definitions are not used in the fabric
(which still uses raw ChaincodeDeploymentSpec). Future CRs
will incrementally use them.

protos/peer/chaincodepackage.proto
----------------------------------
Defines ChaincodeInstallPackage with ChaincodeDeploymentSpec
and endorsements (owners) over it. Key observation- owner signs
(CDS+instantiationpolicy+ownerid)

protos/common/common.proto
--------------------------
introduce CHAINCODE_PACKAGE header type

core/common/ccpackage/ccpackage.go
----------------------------------
Defines two packaging functions - one for a owner
and another for installer.

Change-Id: Ie4b9ebb4aa08957f30c72dd576c90b119e4ea912
Signed-off-by: Srinivasan Muralidharan <muralisr@us.ibm.com>