Add FreeType and zlib

I added FreeType and zlib, and added a sample (derived from one in the official FreeType tutorial) which uses the Droid Sans font and displays rotated text on the screen. Unfortunately I can't include libndls.h because I'm using Newlib headers, so I had to copy some stuff from it. (Of course, once you finish merging Fabian's changes, that will no longer be a problem.)

Also I removed Ndless-SDK/include/LICENSE.txt and added proper "public domain" headers, since not everything in the include directory is public domain.