Progress indicator

[sohidaka]

When forward/backward transformation takes long, progress indicator would help to estimate the response time.

[massimotisi]

A possible solution would be to divide forward transformation in two tasks with two progress monitors: 1) Executing forward transformation (that terminates fast and returns the target model to the user), 2) Preparing backward transformations (that is longer in background).

[yvrng]

A ProgressMonitor is available in the Context that is transmitted across the different tasks. It can be retrieve with the Context.monitor() method.
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