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Added Node.js library link

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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outdated JS.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.

fix init.d script copy duplication

Copy init.d script twice in the guide. Deleted the second one.

Replace 6.0-to-6.7.md with 6.0-to-6.8.md

Fix typo: Confiure -> Configure

Add scoping to ldap lookup when only dn given

rake setup

Add alias `rake setup` to `rake gitlab:setup`
Mention in developer docs

 Add uniq db index on project_id+iid

Because:
* its faster
* it solves problem with repeating iid's in one project

gitlab.yml description Typo

Adjust MySQL limits for existing installations