fix: pre-compiled header conflicts across different build configurations
Merge branch 'master' of https://github.com/tszirr/assimp
Fixed mingw cross compiler issues.
Fixed building simple opengl texture example with mingw.
Removed unreferenced variables.
Fixed class attribute initialization order.
Fixed variable assignment values.
Removed noops and warnings on unused variables.
Added conditions for compiler oder build mode dependend code.
Added parenthesis for explicit operator evaluation priority.
Replaced function parameters with correct literals.
Removed invalid extern keyword.
Merge pull request #185 from adrianbroher/master

Fix various errors and warnings that prevented build assimp_view as linux to win32 cross compile.
Adding tessellation support for new Blender 2.6 polygons

- Added BlenderBMesh.cpp/h which contains a class to convert a BMesh to an old style tri/quad mesh
- Added BlenderTessellator.cpp/h which contains a class to tessellate the poly loops contained within a BMesh
Update CMakeLists
BlenderTesselator: disable GLU tesselation code by default.
BlenderTesselator: Fix OffsetOf() macro
Merge pull request #187 from assimp/blender-26-poly

Blender 2.6 poly format patch, by @kittencataclysm. This enables reading the new mesh format in Blender 2.6 and thus fixes a whole bunch of reports related to recent Blender versions.
SortByPType Posprocessing crashed for crappy models with degenerated geometry

Which models crashed before the fix?:
The crash was observed for files with the following properties:
1. They contain >=1 meshes
2. They were loaded with SortByPType option
3. They only contained degenerated meshes, so that these were skipped SortByPType

What is improved by the fix?:
Obviously, the affected models were crappy anyway and will still produce empty output after the fix. However, the fix avoids the heap-corruption, which couldn't be solved by try/catch from outside and had the annoying effect that a whole scene with hundreds of individual models could crash due to a single crappy one.

Why did it crash before?
The SortByPType deleted some exluded meshes, but didn't reset the pointers in pScene. After throwing the DeadlyImportException (no remaining meshes), remaining meshes were deleted => Excluded meshes were deleted twice.
3DSLoader: Skipped chunks of size 0