master is now 2.4.0dev
large U3D-related patch by Michael Vidiassov

- added some options for the 3D-Annotation:
      - activate Toolbar, Navigation Panel choice
      - allow own Appearance Stream
      - set compression
      - set activation on Page Open ("PO")
- Added set PDF version to 1.7 (therefore small change in encryption)
- added some options for 3DView: Crosssection Dict, changed Node handling for more flexibility, set camera by matrix
- set compression for JavaScript
- Link Annotation added Javascript (therefor Dest was chenged to allow to be nil)
- Widget Annotation implemented to blank some elements for printing (simple overpaint them white while printing)
- added some missing Exports (in .def file for windows)
- removed not correct working function HPDF_3DAnnot_Set3DView
- removed not correct working function HPDF_U3D_LoadU3DFromMem (not the one recently added)