Bump govuk-elements-sass to 2.0.0

# 2.0.0

- Remove the images path override from the helpers partial ([PR
#292](alphagov/govuk_elements#292)). This will
break background images that are currently using the `file-url`
function from [the url-helpers partial in the frontend
toolkit](https://github.com/alphagov/govuk_frontend_toolkit/blob/d54c9b2
6d314a6e6cb50ba90f6e96ca50049498f/stylesheets/_url-helpers.scss). As
`$path` will vary from project to project you will need to define this
in your main application stylesheet.
- Bump govuk frontend toolkit to 4.16.1 ([PR
#288](alphagov/govuk_elements#288)). This adds
space key activation to links with a role of button.
- Form validation patterns for conditionally revealing content ([PR
#286](alphagov/govuk_elements#286))
- Centre text on full-width buttons ([PR
#289](alphagov/govuk_elements#289))
- Lint JS code using [StandardJS](http://standardjs.com/) ([PR
#290](alphagov/govuk_elements#290))

*This version deprecates external link styles. If your service has user
research that indicates that external links are useful (or not) then
we’d like to hear from you either on Slack,
[digital-service-designers](https://groups.google.com/a/digital.cabinet-
office.gov.uk/forum/#!forum/digital-service-designers) or [opening an
issue](https://github.com/alphagov/govuk_elements/issues/new).*

# 1.2.2

- Bump govuk frontend toolkit to 4.14.4 (PR #278)
- Add a .column-full class (PR #270)
- Add a file upload example (PR #268)
- Remove the blue outline from the main content area (PR #265)
- Fix legend text wrapping in IE (PR #248)

# 1.2.1

- Consistent spacing underneath block labels and toggled content (PR
#229)
- Remove underlines from abbreviations in Firefox (PR #241)

package.json

@@ -21,7 +21,7 @@
     "express-nunjucks": "^0.9.3",
     "express-session": "^1.13.0",
     "express-writer": "0.0.4",
-    "govuk-elements-sass": "1.2.0",
+    "govuk-elements-sass": "2.0.0",
     "govuk_frontend_toolkit": "^4.18.2",
     "govuk_template_jinja": "0.18.3",
     "grunt": "0.4.5",