This will try and list all possible "conflict" cases that can happen in a model comparison. For each use case, we will consider
two models, "left" and "right", with their common ancestor "origin".

All of the following 4 categories apply to both "attribute" and "reference" changes

a - Left : Changing value of single-valued feature. Right : Deleting the containing element.
	a1 - Changing value "origin" to "left".
	a2 - Setting value to "left".
	a3 - Unsetting value.

b - Left : Changing value of single-valued feature. Right : Changing to another value the same single-valued feature.
	b1 - Left : Changing value "origin" to "left". Right : Changing value "origin" to "right".
	b2 - Left : Changing value "origin" to "left". Right : Unsetting value. 
	b3 - Left : Setting value to "left". Right : Setting value to "right".
	b4 - Left : Unsetting value. Right : changing value "origin" to "right".
	b5 - Setting value to "leftAndRight" on both sides
	b6 - Unsetting value on both sides

c - Left : Changing value of multi-valued feature. Right : Deleting the containing element.
	c1 - Adding value "left1" to feature.
	c2 - Removing value "origin1" from feature.
	c3 - Setting value "left1" into empty feature.
	c4 - Clearing all values from feature.
	c5 - Moving value "origin1".

d - Left : Changing value of multi-valued feature. Right : Changing the same value in an incompatible way.
	d1 - Left : Removing value "origin1" from feature. Right : Moving value "origin1".
	d2 - Left : Moving value "origin1". Right : Removing value "origin1".
	d3 - Left : Moving value "origin1". Right : Moving value "origin1" to a different index.
	d4 - Clearing all values of this feature on both sides
	d5 - Removing value "origin1" from both sides
	d6 - Moving value "origin1" to the same index on both sides

These only apply to reference changes

e - Adding reference towards deleted Notifier.
	e1 - Within single-valued reference.
	e2 - Within multi-valued reference.
	e3 - Add a single-valued reference on the right side to a node that has been deleted on the left side.
	
f - Changing containment feature of Notifier to two distinct features in left and right.
g - Changing container of Notifier to two distinct Notifiers in left and right.

h - Changing container of Notifier to a deleted Notifier.
	h1 - Within single-valued containment reference (refinement of case 1).
	h2 - Within multi-valued containment reference (refinement of case 3).

k1 - Real Add Conflict, containing pseudo conflict (must be detected as real conflict).
k2 - Real Add Conflict, containing pseudo conflicts (must be detected as real conflicts).
k3 - Real Add Conflict, containing pseudo conflict, containing pseudo conflict (must be detected as real conflict).
k4 - Real Conflict (not add), containing pseudo conflict (must not be detected as real conflict).
	(see https://bugs.eclipse.org/bugs/show_bug.cgi?id=442897)

Ecore specific?

- Setting two different attributes as "idAttribute" in left and right.
- Setting two distinct enum literals to the same "value" in left and right.