synched with trunk at revision 28841
added RecastNavigation library as extern project
added converting  mesh of game object to Detour StatNavMesh (game object is defined by property "navmesh")
- added new game object type for navigation mesh
- added py api for path finding and ray casting
- set svn properties for KX_Pathfinder
EOL to native
Added new actuator type for following steering behaviors: seek, flee, path following; renamed KX_Pathfinder to KX_NavMeshObject
synched branch with trunk at revision 29109
added item thumbs_blend.c into the project BL_imbuf (vc9)
added obstacle avoidance code; object movement is implemented via setting velocity
Added segment obstacles, creation obstacles for walls of navigation mesh
Added parameters for obstacle avoidance simulation: for object - flag for creation representation in simulation(OB_HASOBSTACLE) and obstacle radius (obstacleRad), for scene - obstacle simulation type (obstacleSimulation); added ui for new parameters
Added debug circle rendering (extended OglDebugLine to OglDebugShape, created new function KX_RasterizerDrawDebugCircle)
- added acceleration and turn speed parameters for obstacle simulation
- added debug visualization for object velocities
- registration obstacle in game object
- creation obstacle on object replication (including navmesh object)
- creation object transform for navigation mesh directly from blender object instead of using SGNode world transform (because SGNode doesn't exists yet when building navmesh  on ProcessReplica)
Added:
- obstacle culling for correct simulation in 3d
- flag for steering actuator termination on reaching target
- path recalculation period
- advance by waypoints (for path following)
don't add obstacles for navmesh walls in the path following mode
- added new modifier to create navigation mesh (it's empty now)
- added parameters for navmesh modifier
added actual creation of  navigation mesh for navmesh modifier
Added operator for generating navigation mesh for selected blender objects
Work on conversion of the navigation mesh: we build navmesh directly from blender mesh using custom face data, when no custom data provided we use RAS_MeshObject interface