Serialize last_fetched_at as a string with seconds
Add an index for Note#updated_at
Allow nested files in wiki.
Default last_fetched_at to 0 for old clients

Users who have not refreshed their browser tab will poll GitLab using
outdated JS. This change makes the server fall back to the old behavior
(send all comments) for old clients, instead of throwing an exception
for old clients.
Remove markdown notation from notification emails
Added Node.js library link
Merge branch 'notes_finder_updated_at' into 'master'

NotesFinder filters by updated_at
Merge branch 'master' of https://github.com/gitlabhq/gitlabhq
Add apple-touch-icon-precomposed.png because of 404 on iOS devices
Merge pull request #6891 from moul/patch-1

Added Node.js library link
Merge pull request #5962 from skv-headless/editing-preview

editing preview
Add new entries to CHANGELOG
Remove redundant signin link from signin page.
Merge pull request #6876 from dblessing/fix_broadcast_text

Fix unclear text in broadcast message view.
Merge pull request #6877 from Nighoo/repository_push_email.text

do not html encode plaintext part of emails for push notifications
Do not refresh notes on hidden tabs
Refresh notes when the page becomes visible
Add document.hidden improvement to CHANGELOG
Merge branch 'refresh_unless_hidden' into 'master'

Refresh Notes unless the tab is hidden
Remove empty line.