Added rudimentary screen scrolling in one direction

This will need to be extracted into a camera module, because there will
be logic governing its behaviour later.
Invisible blocks in the maaaaaaaap!

Christopheeeeeeer!!!
Clamped the max speed, and scroll speed
Merge pull request #3 from variousauthors/glitches

Glitches!
Merge branch 'master' into collision
Inserted glitches into level and restart
Move map into its own class function
Some assets and the TEsound library
Aww yiss, sounds!
Updated the maps to a recent version

FOR TESTING
Documentation, and non-double music!
Better-sounding music file
Woo! The player moves to the next level or dies

based on their actions. Now to.. parameterize!
More assets.
Added an undesirable sound
OK! Levels are instantiated with callbacks

They arrange whether you die, or glitch, or what
Made the "SubsequentLevels" work
Levels rock now
Merge branch 'master' into Sounds!

Conflicts:
	main.lua
	map.lua
Merge pull request #4 from variousauthors/Sounds!

Sounds!