Added some GUI elements and reworked some artwork

Hey, it's been a couple of weeks I did not update there so here we go. 
I started creating some GUI elements and added them. I also started reworking my cards and adding new ones. To have my first level more complete I'll need around 30 different cards and so far I made 13 of them. 
I did not implemented all of them yet as I'll need to rework also the current level to make it bigger with new areas and stuff to do.