Added a basic set of source and build files for Linux

|BUILD CONFIGURATION|
[Linux]
* Added a basic Makefile, which uses the ZED library

|SOURCE|
[Linux/Main]
* Nothing of note is handled in main, the program exits as soon as it is run,
  for now
Added a base Window class

|SOURCE|
[Common/Window]
* The Window class is to be inherited by different windowing systems