Image size updates

Added really big doge
Added optional 'size' query parameter (200x300, 400X100, 500, etc.)
updated readme install instructions
implemented caching lru-cache
added query 'image' option

moved images to 'images' dir
added dogecoin picture, re-enabled dogeface
moved image default size and filename to config object
crappy index page + fixed static routing
Merge branch 'caching'

Conflicts:
	presentors/doge.coffee

added basic lru caching functionality
added support for different image options
fixed bug preventing static content from loading
added *really* basic functionality to index page