Add warning if javascript is disabled

[noahmanger]

The datatable filters don't work without javascript. We should either have a server side fallback or just show a warning. While we're in beta I think it's fine to show a warning.

[msecret]

Should this warning only appear on certain pages (such as the ones that have broken functionality)? What should the UI be for the warning?

[noahmanger]

What do you think about just replicating the old IE warning we're using? It would be universal, but I think that's ok. We could keep the wording sufficiently broad, like:

Javascript Required
OpenFEC uses Javascript to provide the best possible user experience. Please enable Javascript in your browser or visit fec.gov.

@emileighoutlaw what do you think about the language?

For an example, here's what Facebook uses:

JavaScript Required
We're sorry, but Facebook doesn't work properly without JavaScript enabled. If you can't enable JavaScript try visiting the mobile-optimized website.

[jmcarp]

👍 to a universal warning. Lots of stuff is going to break without JS, and I don't want to deal with the overhead of updating per-page warnings when we add or remove JS from different pages.

[msecret]

fecgov/openFEC-web-app#260

[jmcarp]

Merged.