Updated PipelineViewPresenter to reset mappings.

Updated PipelineViewPresenter to reset mappings, which may be invalid, when Apps are rearranged in the pipeline.
Added PipelineStepEditorView and PipelineAppOrderView.

Refactored the App ordering grid from the PipelineView into its own PipelineAppOrderView.
Added a common PipelineStepEditorView interface that the PipelineInfoEditor, PipelineAppOrderView, and PipelineAppMappingView could implement.