Back to stretched custom shader material
Working tiling using fract() on position, but only on horizontal faces and with hardcoded material

Screenshot: http://i.imgur.com/jLKX9Np.png
Use dot product for tileUV, fixes vertical faces

Formula from http://0fps.wordpress.com/2013/07/09/texture-atlases-wrapping-and-mip-mapping/
Pass tileOffset as uniform; cleanup