Merge pull request #1741 from loebl/doc/find_degenerates_parameters

Add note to aiProcess_FindDegenerates about AI_CONFIG_PP_FD_CHECKAREA

include/assimp/postprocess.h

@@ -360,6 +360,11 @@ enum aiPostProcessSteps
      *       and line meshes from the scene.
      *   </li>
      * </ul>
+     *
+     * This step also removes very small triangles with a surface area smaller
+     * than 10^-6. If you rely on having these small triangles, or notice holes
+     * in your model, set the property <tt>#AI_CONFIG_PP_FD_CHECKAREA</tt> to
+     * false.
      * @note Degenerate polygons are not necessarily evil and that's why
      * they're not removed by default. There are several file formats which
      * don't support lines or points, and some exporters bypass the