Add .ruby-version to 1.9.3

We don't actually execute any Ruby in this project, except for during
the build process.

I think this will alleviate some issues when installing gems:

    sudo: no tty present and no askpass program specified
    Sorry, try again.

    Gem::Exception: Cannot load gem at [/var/lib/gems/1.9.1/cache/sass-3.2.12.gem]
Use bundle exec when building Sass in production

So that we use the copy of the sass binary in vendor/cache.
Make module_actions JavaScript more reusable

Rename module_actions to popover (à la iOS) so that we can use it
for a dashboard's related links. Include a basic first pass of
popover in related_pages.
Move popover related Sass into a single file

Use mixins to include it in multiple places.
Reorganise index.scss into logical groups

Also rename module_actions to module_more_info for ease of scanning.
Merge branch '62545960-hide-related-links-small-screens' of github.com:alphagov/spotlight
Add first version of "division of procurement" graph
Fix neg number bug in roundToSignificantFigures

And make it a method on View.
Move rounding changes tests into correct place

And remove one duplicate.

And tidy whitespace on an object, remove unused thresholds (they're
duplicated below).
Change rounding thresholds from 500 to 1000

For all orders of magnitude.

I think there's an opportunity for some refactoring here.
Test against (what i think will be) the real data after the fix
What the actual fix may loook like
Fix json for working response
Just use utc
Get moment should fix things... but where does moment come from?
fix tests - we will always use utc
remove logs
Merge branch 'master' into test-backdrop-data-fixes

Conflicts:
	app/support/backdrop_stub/response_fetcher.js
Show quarterly ticks on x-axis for monthly data over long timeframe.

When we have monthly data going back more than 15 months, use quarterly ticks.

I've over-written the "month" config in graph.js. We don't seem to be using
this anywhere in the live app, or testing it, so I think it's OK to overwrite.
But I'd be grateful if someone with more Spotlight experience could check.
Amend graph title