Make more explicit the dependence of PointCloudViewer on VTK and on I…

[mehdi-benallegue]

…O package of PCL

I had issues with incomplete versions of PCL and no VTK installed.

[k-okada]

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Build Log
last 10 lines

[...truncated 8568 lines...]
    at org.jenkinsci.plugins.ghprb.GhprbRepository.createCommitStatus(GhprbRepository.java:122)
    at org.jenkinsci.plugins.ghprb.GhprbBuilds.onCompleted(GhprbBuilds.java:118)
    at org.jenkinsci.plugins.ghprb.GhprbBuildListener.onCompleted(GhprbBuildListener.java:27)
    at org.jenkinsci.plugins.ghprb.GhprbBuildListener.onCompleted(GhprbBuildListener.java:12)
    at hudson.model.listeners.RunListener.fireCompleted(RunListener.java:202)
    at hudson.model.Run.execute(Run.java:1783)
    at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:43)
    at hudson.model.ResourceController.execute(ResourceController.java:98)
    at hudson.model.Executor.run(Executor.java:410)

Test FAILed.