- kicked the Irrlicht idea (this is not going to work like I thought)

- kicked the Irrlicht idea (this is not going to work like I thought)
- removed Irrlicht and ZLIB requirements from the makefiles (both handled by Qt5)
- updated all missing language tags (English/German)
- added DatWindow skeleton (will be a dat file viewer and later an editor)
- added ObjectWindow skeleton (will be a 3d object viewer/editor for meshes, BSP and highfields)
- added a small tool for BSP file viewing (just a "can I do it?" study)
- added engine subpart, here all the mesh, highfield and BSP stuff will go
- fixed some minor bugs (wrong connections, etc)
- some code cleanups