Merging two different versions does not adjust some conflicting nodes

[dimitar-asenov]

In some situations it is possible to perform an automatic merge and get inconsistent results. For example, if two methods have been added to the same class at the same location, but in two different versions. Currently they will not conflict and will be merged automatically even though they have the same (x,y) coordinates in the visual representation of the class grid.

There needs to be a way to detect and remedy this situation. In the particular case above the position in the grid should just be adjusted. In general the version control framework should be extensible with hooks to deal with such situations.