stripping out all but the necessary stuff from the web-server.  Bumping to 500 max-waiting.
adding printf to make sure we can see it start.
removing the Racket note in the 404.
Retry on 503
adding 503 tests
updating the startup scripts
enabling connection-close to work around memory issue.
explicit setting connection close to #f; EC2 load balancing behaves very badly under #t
switching back to closing: I'm seeing enormous memory usage
added all triangle functions
removed commented-out 'vertex-triangle' function
Merge branch 'master' into stable

Incorporated Emmanuel's work into stable, since the image library upgrades
rely on it.
The compiler-service.rkt and server-startup.sh scripts are as they were
in stable.

Conflicts:
	compiler-service.rkt : kept '--ours'
	server-startup.sh : kept '--ours'
Merge branch 'image-library' into stable
we need to be sure the image is absolutely positioned, otherwise it w…
Add semaphore to make requests serial.
applied Eric's semaphore change to compiler-service.rkt
add the triangle/xxx family of functions, and unify all the triangle-creating functions in world.js
Merge branch 'master' into stable

This should end the problems with diverged master and stable branches.