Provides JFace support for long-running operations.

## Package Specification

Long-running operations must be dealt with specially in order to keep the UI helpful and responsive. Typically this involves temporarily disabling most controls and displaying a busy cursor and progress indicator; while the operation is in progress, the only requests that will be accepted will be ones to cancel the operation.

The `IRunnableWithProgress` interface should be implemented by any class whose instances are intended to be executed as long-running operations. These objects can then be run in any runnable context (`IRunnableContext`), including such standard JFace UI components as application windows (`ApplicationWindow`), wizard dialogs (`WizardDialog`), and progress monitor dialogs (`ProgressMonitorDialog`). The utility class `ModalContext` defines the basic mechanism and UI event loop for modal operations.