typos fixed
Merge branch 'master' of dev.gitlab.org:gitlab/gitlabhq into grammar_fixes
Merge branch 'grammar_fixes' into 'master'

Grammar fixes

fixed typos in groups messages
Required shell version is now 1.9.4.
Merge branch 'master' of dev.gitlab.org:gitlab/gitlabhq
Version to 6.9.0
Add missing lines in update guide.