[429682] Use a map with collection values instead of a multimap

Change AbstractInterpretedExpressionQuery (and subclasses) to use an
explicitly managed Map<String, Collection<String>> to store definitions
instead of a Guava-specific Multimap.

Bug: 429682
Change-Id: I22fa425694b2c34feb651d5f2ca8ccaab10ebf27
Signed-off-by: Pierre-Charles David <pierre-charles.david@obeo.fr>
[430263] Remove the ModelingProjectManagerStartup - Clean step

This startup extension implies that if Sirius is installed, a large part
of
Sirius plugins are getting loaded and started even if your are not using
it.

This commit is a first cleaning step to dissociate the core of this
change:
* Change behavior when a file is removed in a modeling project: Now
there is a validation launched when a reresentations file is deleted in
an invalid project.
* The method ModelingProject.getMainRepresentationsFileURI now marks
this project as invalid and adds a marker on it, if it is considered as
invalid (no or many representations files).
* The method InitializeModelingProjectJob.initializeModelingProjects()
does not add marker anymore (it is done by
ModelingProject.getMainRepresentationsFileURI()).

Change-Id: I9ac762e5a99867dfc592f0b43b51277507b20d86
Signed-off-by: Laurent Redor <laurent.redor@obeo.fr>
[430263] Remove the ModelingProjectManagerStartup startup extension

This extension implies that if Sirius is installed, a large part of
Sirius plugins are getting loaded and started even if your are not using
it.

The sessionManagerListener of ModelingProjectManagerImpl, previously
added by this extension point, is now added during the loading of the
first session.
The initialization of a modeling project (detect if the modeling project
is valid, ie with one and only one representations file) is now done at
the first access of this project and not at the Eclipse start.

Warning: If the Sirius Content Management is active (for example in
"Project Explorer"), Sirius plugins are getting loaded and started even
with this fix.

Change-Id: I3c3c3891bca0f2531935931b8ad97abaef01b320
Signed-off-by: Laurent Redor <laurent.redor@obeo.fr>
[430263] Replace the Sirius decorator by a more complete LabelProvider.

The current Sirius decorator ("org.eclipse.ui.decorators" extension
point) implies that if Sirius is installed, a large part of Sirius
plugins are getting loaded and started even if your are not using it.
This decorator adds a decorator on semantic resources of non Modeling
project. This is now done by the SiriusCommonLabelProvider.

Warning: If the Sirius Content Management is active (for example in
"Project Explorer"), Sirius plugins are getting loaded and started even
with this fix.

Bug: 430263
Change-Id: I7cc11ec343b54a12a58531c5eb366a88d5843987
Signed-off-by: Laurent Redor <laurent.redor@obeo.fr>