[MNG-3679] Adding integration test, and enabling integration tests of two other previously fixed issues.
maven/core-integration-testing/trunk/core-integration-tests/src/test/java/org/apache/maven/integrationtests/IntegrationTestSuite.java
maven/core-integration-testing/trunk/core-integration-tests/src/test/resources/mng-3679-pluginExecIdInterpolation/