Update index of feature flags
Update index of feature flags

Made it clear the pages are about feature flags,
and not documentation.

stoplightio/gitlabhq,stoplightio/gitlabhq,mmkassem/gitlabhq,mmkassem/gitlabhq,stoplightio/gitlabhq,mmkassem/gitlabhq,mmkassem/gitlabhq,stoplightio/gitlabhq