REVIEW-130 Moved out the help tasks implementation to a separate project. 1. The new subproject is called 'diagnostics' (follows an existing convention of the package names). New subproject contains help task implementations (including dependency report tasks). 'reporting' subproject only contans the reporting API. 2. Added the help tasks implementation on the integTestRuntime classpath for every project with integTests. This way we avoid surprises that 'help' or 'tasks' task is missing when one writes a unrelated integ test.