Export material and texture with the mesh

Export now also .material and .png files to media/material
subdirectories.

Export material and texture with the mesh

Export now also .material and .png files to media/material
subdirectories.

Put the MIT Licence in all the source code files

Added the file LICENSE.txt to the root, containint the MIT license.
Added the license also to all the files, instead of the one relative to
simplex noise (simplexNoise.h and simplexNoise.cpp)