feat(waypoints): manage edges orientation when cycle exist in the Grid

[tbouffard]

Also fix some orientations involving gateways.

refactor:

• introduce code to compute edge terminal points coordinates
• improve logs
• static import for all Direction calls

WaypointsComputer test refactor:

• explicit usage of merge or split gateways
• rename: use join instead of merge for gw for consistency with the layout algo

Add specific log4j2 config file for tests

[tbouffard]

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