Basic handling for bad URLs

[medied]

Here's what I found:

• Looks like there is no correct way (or even working?) way of handling real 404s right now with Iron Router.
• There's an issue along with its respective PR that have both been open for a while.
• This all points to the fact that Iron Route may be dying out to FlowRouter:

One other difference—and perhaps the elephant in the room—is that the Iron Router project has started to slow down a bit in terms of active development and response to issues. While there hasn't been any official statement around whether or not work on the project will continue, many have expressed concern about this. Flow Router, in contrast, is seeing a lot of active development

With that in mind, this PR does a very basic handling of bad URLs: it renders a notFound template but still gives a 200 HTTP status. All URLs with the form of localhost:3000/somethingrandom or localhost:3000/some/randomorunknonw/path render the notFound template. Note that this takes care of localhost:3000/peer (which was a TODO in routes.js).

URLs with the form of localhost:3000/vote/whatver, localhost:3000/peer/whatever, etcetera, currently just show an empty template (with no errors). I'm suggesting to leave it this way for now, because the current solution just feels too hacky. Longer term, it might be best to migrate to FlowRouter.

Fixes #84

[santisiri]

It's in the Issues to do a migration to FlowRouter. It does seem to have become the standard for meteor since its faster and with more community support right now.