Some graphics stacks just suck (like AMD + Mesa), so we have to clear the frame buffer on each frame, otherwise garbage and/or flickering appears on undrawn areas.
Fixes#53.
Replaced all references to simulation with emulation
Updated copyright year
Updated .gitignore to reduce chances of random files being uploaded to
the repo
Added .gitattributes to normalize all text files, and to ignore binary
files (which includes the logo and the NEC PDF)