[mr2833] Update recast/detour to revision 351

Also removed RecastDemo, any way not used. If you need demo, download it by himself from http://code.google.com/p/recastnavigation/
[mr2834] Tune Recast & Detour

Based on CMaNGOS (author Cyberium) and TC (author kaelima)
[mr2835] Update MMap Builder for new Detour navmesh generation (settings and code style)
[mr2836] Tune MMapBuilder for more realistic path generation
[mr2837] Update VMap extractor
[mr2838] Update Extractor
[mr2839] Update VMAP and MMAP versions
[mr2840] Some improvements
[mr2841] Use new Detour return value format and some code style
[mr2842] Add ".mmap path go" chat command and rename "true" option to more exp…
…licit "straight".

Author Cyberium
[mr2843] Fix Prayer of Mending (spell 33076) "jumps", close #1364