Issue 8 basic validation

Added basic validation for form and JSON submission. Used the [voluptuous](https://github.com/alecthomas/voluptuous) library for this, which offers a pretty 
nice API for specifying the structure of Python data structures.

Additionally, tidied up views.py and the respective templates to avoid using a bizarre _additional_info function.

fixes #8 
Yeah, now that I think about it, I think I don't have beef with PEP8—I was
thinking about Google's style guide for Python or JS. Autopep8 could be
worth it, then.


On Tue, Aug 19, 2014 at 11:14 AM, Ryan Williams <notifications@github.com>
wrote:

> In cycledash/helpers.py:
>
> > @@ -0,0 +1,54 @@
> > +import re
> > +
> > +
> > +
>
> OK. I'm curious what gets gnarly with PEP8. Here is autopep8
> <https://github.com/hhatto/autopep8> btw.
>
> If PEP8 is what we say we are using, and there is an easy tool to
> auto-format code accordingly, I don't really see the argument for not doing
> it.
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/hammerlab/cycledash/pull/17/files#r16420826>.
>