Unterteile reguläre Dreiecke nicht weiter

Closes #7

See merge request !9

Fix default path for file open

Closes #11

See merge request !4

Rewrite getPatchIndexBuffer

Closes #15

See merge request !6

Resolve "findRegular ist langsam"

Closes #9

See merge request !8

Resolve "Baue neighbors map auf der GPU"

Closes #16

See merge request !7

These models are not closed, they have at least one edge that is not
connected to another edge.

buddha, bunny and dragon were not tested as they have a lot of
triangles.

Resolve "Nachbarn sollten nur einmal berechnet werden"

Closes #13

See merge request !5