Include ImgLib1

According to http://fiji-devel.54424.x6.nabble.com/Re-TrakEM2-Fiji-dependency-issues-td2592.html#a2593, there are no plans to port TrakEM2 to ImgLib2. However, ImgLib1 is a dead project. Therefore, let's just include all of ImgLib1 into TrakEM2 for now.

The only complication is that the 3D Viewer needed to get rid of the ImgLib1 dependency and sprouted a new API to let TrakEM2 perform triangulations on ShapeListImages. Hence we need to merge https://github.com/fiji/3D_Viewer/pull/11 before this PR.