title: Getting and error "Cannot complete the install because one or more required items could not be found" in oomp installer
body: <p>Trying to setup eclipse development environment using <a href="https://www.eclipse.org/community/eclipse_newsletter/2014/may/article3.php" rel="nofollow">oomph</a> but getting an error <strong>"Cannot complete the install because one or more required items could not be found"</strong></p>
  
  <p>See stack trace:</p>
  
  <pre><code>    ERROR: org.eclipse.equinox.p2.director code=10053 Cannot complete the install because one or more required items could not be found.
  at org.eclipse.oomph.targlets.internal.core.TargletContainer.forceUpdate(TargletContainer.java:778)
  at org.eclipse.oomph.setup.targlets.impl.TargletTaskImpl$4.run(TargletTaskImpl.java:1128)
  at org.eclipse.oomph.util.pde.TargetPlatformUtil.runWithTargetPlatformService(TargetPlatformUtil.java:119)
  at org.eclipse.oomph.setup.targlets.impl.TargletTaskImpl.perform(TargletTaskImpl.java:1036)
  at org.eclipse.oomph.setup.internal.core.SetupTaskPerformer.doPerformNeededSetupTasks(SetupTaskPerformer.java:3021)
  at org.eclipse.oomph.setup.internal.core.SetupTaskPerformer.access$1(SetupTaskPerformer.java:2964)
  at org.eclipse.oomph.setup.internal.core.SetupTaskPerformer$WorkspaceUtil$1.run(SetupTaskPerformer.java:4160)
  at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2240)
  at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2267)
  at org.eclipse.oomph.setup.internal.core.SetupTaskPerformer$WorkspaceUtil.performNeededSetupTasks(SetupTaskPerformer.java:4154)
  at org.eclipse.oomph.setup.internal.core.SetupTaskPerformer$WorkspaceUtil.access$0(SetupTaskPerformer.java:4152)
  at org.eclipse.oomph.setup.internal.core.SetupTaskPerformer.performNeededSetupTasks(SetupTaskPerformer.java:2955)
  at org.eclipse.oomph.setup.internal.core.SetupTaskPerformer.performTriggeredSetupTasks(SetupTaskPerformer.java:2930)
  at org.eclipse.oomph.setup.internal.core.SetupTaskPerformer.perform(SetupTaskPerformer.java:2861)
  at org.eclipse.oomph.setup.ui.wizards.ProgressPage$9.run(ProgressPage.java:555)
  at org.eclipse.oomph.setup.ui.wizards.ProgressPage$11$1.run(ProgressPage.java:681)
  at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)
  ERROR: org.eclipse.equinox.p2.director code=0 Software being installed: artificial_root 1.0.0.v1467382214442
  ERROR: org.eclipse.equinox.p2.director code=0 Missing requirement: Infocenter_feature Feature 1.0.0 (org.eclipse.help.infocenter_feature.feature.group 1.0.0) requires 'org.apache.commons.el 0.0.0' but it could not be found
  ERROR: org.eclipse.equinox.p2.director code=1 Cannot satisfy dependency:
  ERROR: org.eclipse.equinox.p2.director code=0 From: artificial_root 1.0.0.v1467382214442
  ERROR: org.eclipse.equinox.p2.director code=0 To: org.eclipse.help.infocenter_feature.feature.group 0.0.0
  
  Took 2610 seconds.
  There are failed tasks.
  Press Back to choose different settings or Cancel to abort.
  </code></pre>
  
  <p>Any clues or pointer to resolve this and successfully setup eclipse dev environment using oomph?</p>