Small fixes.

Vector construction not yet finished.
The boundaryEdge object now contains a pointer to the triangle where
the edge belongs, allowing us to calculate the normal vector later on
(TODO)
Revert "Small fixes."

This reverts commit 984b0ca1f8e1a8fee9345f61c63d932a7cea0e4b.
Revert "Revert "Small fixes.""

This reverts commit 9570f790bed313d2e1a83724dbe4bc9bf973fb4f.
Revert "Small fixes."

This reverts commit 984b0ca1f8e1a8fee9345f61c63d932a7cea0e4b.