Generalize "load *.html files first" hack

Now any plugin can request that its files be treated as "templates" by
setting an isTemplate flag.

(This API is just as supported as you'd expect based on the fact that
you still can't access it without calling a function which starts with
"_transitional_".)

Tested by renaming leaderboard.js to a.js and confirming that it still
works (and that it *doesn't* if templating does not set isTemplate).
Remove old, unused html5-tokenizer package
Make Blaze packages internal
Don't rewrite URI with a defined protocol (ie http(s) or data) Use the node `url` module to parse the URI
upgrade mongo to 1.4.0-rc9 from a fork of 1.3.19
checkpoint towards running multiple mongods

still need to make onExit blow it all up