Prevent confusion by sharing of signed page urls

Also:

• Add a theme colour for home page apps on Android
• Add the ability to search archived signatures from the admin
• Add stats about emails being used twice
• Update holiday period messaging

Upgrade Rails to 4.2.11

Merge pull request #671 from alphagov/rails-4-2-11-update

Update Rails to address vulnerability in Active Job

Improve signature thank you page

Add some messaging about waiting 24 hours and checking spam folders
for the confirmation email.

Make signature verification idempotent

Merge pull request #667 from alphagov/make-verify-idempotent

Make signature verification idempotent

Don't show 'signatures by x' on rejected petitions

1.5.7

Merge pull request #666 from alphagov/only-show-signature-data-for-pu…

Strip hypens and en/em dashes from postcodes

Merge pull request #665 from alphagov/sanitize-postcode-dashes

Strip hyphens and en/em dashes from the postcode before validating

Petition map updates

• Fix archive search results to link directly to the archived url and not the original url
• Redirect original url to archive url now maintains JSON format
• Added a petition map link to closed petitions
• Added a petition map link to archived petitions that are applicable
• Petition map urls now use https

Improved feedback message templates

Added a HTML template that auto-links a petition URL and/or email address

Government response date

• Show the date of the government response on the home page and petition page
• Allow option to customise the date of the government response

Google Tag Manager bug fixes

• Add GTM to static error templates