## What changes were proposed in this pull request? During blueprint installation the **BlueprintConfigurationProcessor** inserted stack defaults into **cluster-env** then added cluster-env to the changed list configs. This is wrong in cases when the blueprint already has the stack defaults such as the case of exported blueprints. The result was that blueprint installation got stuck until the server was restarted. I modified the **BlueprintConfigurationProcessor** to mark **cluster-env** updated only when there is a change.
## How was this patch tested? - tested blueprint installation manually - wrote 3 new unit tests - run all unit test for BlueprintConfigurationProcessor [ Full content available at: https://github.com/apache/ambari/pull/2242 ] This message was relayed via gitbox.apache.org for [email protected]
