Go client sdk-based test for integration tests

[g2flyer]

Description

Version of equivalent of (main part) of integration/echo_test.sh and/or integration/auction_test.sh based on a Go Application so travis would exercise also automatically all of client-sdk (part of client-sdk should already be done as part of cli-integration in issue #486.

Setup & Chaincode creation might be best used the script-based version currently used in theses scripts as orthogonal to the actual chaincode application. The chaincode creation could eventually be supplemented by a fully-programmatic version, e.g., as part of issue #488

Probably best done together with #490 given the large overlap?

Link to feature or bug

Link to dependent issues