Changed default status handling to 'log', and show exceptions during synthesis transformations to the user.

[NiklasRentzCAU]

Previously, any code calling Klighd.handle(IStatus) caused the status and possible warnings and exceptions within to not be shown anywhere. This alters that behavior, so that the status is at least logged, matching the default behavior of the previoulsy used Eclipse StatusManager's handle(IStatus) method.

Furthermore, this shows an exception being thrown during a synthesis to the user in addition to logging it, so that errors during syntheses can be tracked down more easily.

[sailingKieler]

Hi @NiklasRentzCAU,
a general question at first: Is the motivation of this change to change the behavior in Eclipse, or in the language server context?

I disagree with this change as productive application would have to spend effort to explicitly suppress this behavior (by trying to inject some wrapping status manager impl).
In dev environments this could easily been done in order to achieve the desired verbosity.

I agree with this change as it follows the behavior of org.eclipse.ui.statushandlers.StatusManager.

[NiklasRentzCAU]

This is for the behavior in the Eclipse context. I can see though that a default verbosity to show the message in a popup might not be what is wanted in general. I'll revert that back and just keep the other change, so that it at least can be viewed in the error log.

[sailingKieler]

Please squash the commits, and I'll be fine with them.