Added 3D model viewer
Interim commit of PLY to STL converter. Stil broken.

Parses PLY okay, still have to write STL output.
PlyToStl converter complete. Seems to work okay.
Cut down on memory usage by using SplFixedArray.

It's still pretty bad. Looking into mysql temporary tables now.
Cut memory usage in half by using a string to store integers.

Looked into using mysql temporary table for vertices but it's too much
data for in-memory tables and everything on disk is just way to slow.
Now we're at ~500megs memory usage for pretty huge PLY files, which
isn't too bad.