Changes: ...

* added Makefile (windows part not yet finished)
* splitted array.cpp in a header file -> include/array.h
* sources/main.cpp only uses include/array.h

Changes: ...

* added teapot.obj
* add array.cpp
* modified main.cpp to use array.cpp

Actually array.cpp is implemented using pointers, but it should use references, since the garbage collector accidentally frees array contents.