Simplify upgrade guide based on 6-4 functionality mentioned by Jacob.
Disable SSL peer verification for all webhooks

SSL peer verification was silently enabled by the HTTParty upgrade in
8a54fda45957b3755f7c06e5c9b955c794488ff1. This patch restores the
previous behaviour of GitLab 6.3 and earlier.
Add second sponsorship message, perfect world.
 Merge branch 'say-media-mention' into 'master'

Say Media Mention

Sponsorship message for https://dev.gitlab.org/gitlab/gitlabhq/merge_requests/388/diffs
 Merge branch 'webhook_verify_none' into 'master'

Disable SSL peer verification for all webhooks

SSL peer verification was silently enabled by the HTTParty upgrade in 8a54fda45957b3755f7c06e5c9b955c794488ff1.
This patch restores the previous behaviour of GitLab 6.3 and earlier.
 Merge branch '6-4-update-guide' into 'master'

Improve 6-4 update guide