Record maven-invoker-plugin failures via junit rather than console

[jglick]

Inspired by a change in jenkinsci/plugin-pom#508. Rather than streaming all the IT logs to the Jenkins build log, capture them in JUnit-format test results instead, and treat any failures as an unstable build. Should make it easier to develop #66 and the like.

[jglick]

For local devs.

[jglick]

For CI. Inspired by a similar profile in pom / plugin-pom.

[jglick]

Lots of noise from MRM like

 [WARNING] Could not validate integrity of download from https://repo.jenkins-ci.org/public/org/kohsuke/stapler/stapler-parent/1.238-SNAPSHOT/stapler-parent-1.238-20160223.022943-3.pom.sha1
 org.eclipse.aether.transfer.ChecksumFailureException: Checksum validation failed, no checksums available
     at org.eclipse.aether.internal.impl.AbstractChecksumPolicy.onNoMoreChecksums (AbstractChecksumPolicy.java:64)
     at org.eclipse.aether.connector.basic.ChecksumValidator.validate (ChecksumValidator.java:107)
     at org.eclipse.aether.connector.basic.BasicRepositoryConnector$GetTaskRunner.runTask (BasicRepositoryConnector.java:460)
     at …
     at org.apache.maven.artifact.resolver.DefaultArtifactResolver.resolve (DefaultArtifactResolver.java:567)
     at org.codehaus.mojo.mrm.maven.ProxyArtifactStore.get (ProxyArtifactStore.java:320)
     at org.codehaus.mojo.mrm.impl.maven.ArtifactStoreFileSystem.get (ArtifactStoreFileSystem.java:328)
     at org.codehaus.mojo.mrm.api.BaseFileSystem.get (BaseFileSystem.java:74)
     at org.codehaus.mojo.mrm.impl.digest.AutoDigestFileSystem.get (AutoDigestFileSystem.java:154)
     at org.codehaus.mojo.mrm.servlet.FileSystemServlet.doGet (FileSystemServlet.java:151)
     at javax.servlet.http.HttpServlet.service (HttpServlet.java:687)
     at …

I suspect this is caused by some old dependencies requesting a range dependency 😠 on Stapler, but have not tracked it down yet.