Build broken out of the box on OS X

[elfprince13]

[ 81%] Linking CXX executable bin/collada2gltf
Undefined symbols for architecture x86_64:
  "_libiconv", referenced from:
      _xmlIconvWrapper in libxml2.a(encoding.o)
  "_libiconv_close", referenced from:
      _xmlFindCharEncodingHandler in libxml2.a(encoding.o)
      _xmlCharEncCloseFunc in libxml2.a(encoding.o)
  "_libiconv_open", referenced from:
      _xmlFindCharEncodingHandler in libxml2.a(encoding.o)
  "_lzma_auto_decoder", referenced from:
      _xz_make in libxml2.a(xzlib.o)
  "_lzma_code", referenced from:
      _xz_decomp in libxml2.a(xzlib.o)
  "_lzma_end", referenced from:
      ___libxml2_xzclose in libxml2.a(xzlib.o)
  "_lzma_properties_decode", referenced from:
      _xz_make in libxml2.a(xzlib.o)
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [bin/collada2gltf] Error 1
make[1]: *** [CMakeFiles/collada2gltf.dir/all] Error 2
make: *** [all] Error 2

I suspect you need to call find_library for lzma and iconv in the CMake configuration, and add them to the target link libraries.