Add generic trace edit

[dvojtise]

Description

Add org.eclipse.gemoc.trace.commons.model.edit plugin with custom label provider.

The provided label providers improves the way the labels are displayed while navigating the generic trace (multidimensionnal trace)

It provides improved label for the following items:

• GenericMSE
• GenericState
• GenericDimension
• GenericParallelStep, GenericSequentialStep, GenericSmallStep
• SingleReferenceValue

in several places, the label is computed using the position of the element in the trace model

Changes

a new helper plugin (org.eclipse.gemoc.commons.eclipse.xtext) has been introduced to gather EObject naming helpers based on xtext (code was initially developped in org.eclipse.gemoc.executionframework.debugger plugins)

Contribution to issues

Closes https://github.com/eclipse/gemoc-studio-modeldebugging/issues/207

[ebousse]

Very nice. Looks good to me, and in any case I believe such a feature cannot break any core feature (eg. executing a model).

[dvojtise]

I hope this feature will help better understand the multidimentionnal trace metamodel and initiate improvement to integrate multibranch trace capabilities ;-)